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Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Carroll 27 39 18 17

Stark 24 41 17 17

Wayne 24 41 18 16

Factor 7: Geography/topography

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8: Jurisdictional boundaries

The Stark County Regional Planning Commission/Stark County Area Transportation

Study (SCATS) is the Metropolitan Planning Organization (MPO) for the CantonMassillon, OH.

-Source: SCATS web page,

http://www.rpc.co.stark.oh.us/scats.html

The area's ozone nonattainment area consists of the following county:

-Stark

Factor 9: Level of control of emission sources

The State provided no information about the level of control of emission sources for this

area.

6.5.4.2 Cincinnati-Hamilton Area

Discussion:

There are five Ohio counties in this Metropolitan area: Brown, Butler, Clermont,

Hamilton and Warren Counties. There are violating monitors in Butler and Hamilton

Counties. EPA agrees with the Ohio EPA’s Option 2 recommendation to include Butler,

Clermont, Hamilton and Warren Counties as nonattainment for the Cincinnati-Hamilton

nonattainment area. Brown County is not included because there are minimal emissions

and population in this county relative to the Metropolitan area. Brown County was also

excluded from the ozone nonattainment area for Cincinnati-Hamilton. There are four

counties that are adjacent to the metropolitan area in Ohio and not included in other

metropolitan areas. These counties are Preble, Clinton, Highland and Adams Counties.

Of these adjacent counties, Adams County merits further review due to the emissions in
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the county. Adams County is more likely to contribute to violations in Scioto County and

the Huntington-Ashland metropolitan area, and is addressed in connection with that area.

Because emissions are relatively low for Preble, Clinton, and Highland Counties, and no

other factor warranted designating these counties nonattainment, the following data

summaries for factors 3 through 9 do not address these counties.

Factor 1: Emissions in areas potentially included versus excluded from the

nonattainment area

County SOx NOx Carbon Crustal Composite

emission score

Boone, KY 14,717 15,794 721 1,068 7.7

Brown, OH 395 2,927 208 520 2.0

Butler, OH 13,204 19,735 956 1,752 9.9

Campbell, KY 860 5,294 285 260 2.8

Clermont, OH 84,599 45,618 1,693 3,916 20.0

Dearborn, IN 56,773 31,138 900 2,121 11.4

Gallatin, KY 350 2,365 100 234 1.0

Grant, KY 210 2,664 182 191 1.8

Hamilton, OH 88,053 58,398 2,780 3,873 30.3

Kenton, KY 1,573 8,365 415 301 4.2

Ohio, IN 113 682 49 89 0.5

Pendleton, KY 597 3,396 139 207 1.5

Warren, OH 895 7,565 743 1,063 6.9

Adams, OH 125,136 52,992 1,435 3,973 19.4

Bracken, KY 52 570 76 94 0.7

Carroll, KY 53,086 26,269 821 2,177 10.3

Clinton, OH 375 2,490 193 583 1.8

Franklin, IN 92 1,335 143 341 1.3
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Harrison, KY 290 1,786 114 225 1.1

Highland, OH 242 1,756 177 498 1.6

Mason, KY 38,142 16,071 562 1,429 7.0

Owen, KY 57 572 126 105 1.1

Preble, OH 428 2,765 228 721 2.2

Ripley, IN 140 2,081 221 507 2.0

Switzerland, IN 251 1,554 101 145 1.0

Union, IN 58 548 68 272 0.6

Urban increment:

Total mass= 2.1 μg/m3

7% sulfates; 15% nitrates; 78% carbon; 0% crustal.

Urban site=211170007;

Rural site=LIVO1 (Livonia)

Factor 2: Air quality in potentially included versus excluded areas

County 2001-2003 Design Value

Butler, OH 16.2 μg/m3

Campbell, KY 14.5 μg/m3

Hamilton, OH 17.8 μg/m3

Kenton, KY 15.0 μg/m3

Preble, OH 13.5 μg/m3

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Boone, KY 93,290 379

Brown, OH 43,464 88

Butler, OH 340,543 729
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Campbell, KY 88,604 583

Clermont, OH 183,352 406

Dearborn, IN 47,333 155

Gallatin, KY 7,836 79

Grant, KY 23,620 91

Hamilton, OH 833,721 2048

Kenton, KY 152,164 934

Ohio, IN 5,804 67

Pendleton, KY 14,815 53

Warren, OH 175,133 438

Adams, OH 27,804 48

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Boone, KY 19,805 44 842

Brown, OH 9,901 53 417

Butler, OH 62,298 39 2610

Campbell, KY 26,658 62 1097

Clermont, OH 50,763 57 1649

Dearborn, IN 10,978 48 607

Gallatin, KY 1,805 50 254

Grant, KY 5,234 51 379

Hamilton, OH 54,833 14 8420

Kenton, KY 44,002 58 1816

Ohio, IN 1,644 59 56

Pendleton, KY 3,704 57 169

Warren, OH 32,089 42 15

Adams 2,578 23 283

Factor 5. Expected growth
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County Percent growth 1990-2000

Boone, KY 49

Brown, OH 21

Butler, OH 14

Campbell, KY 6

Clermont, OH 19

Dearborn, IN 19

Gallatin, KY 46

Grant, KY 42

Hamilton, OH -2

Kenton, KY 7

Ohio, IN 6

Pendleton, KY 20

Warren, OH 39

Adams, OH 8

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Boone, KY 22 41 18 19

Brown, OH 23 40 18 18

Butler, OH 24 40 18 18

Campbell, KY 23 40 18 19

Clermont, OH 23 40 18 18

Dearborn, IN 23 40 18 19

Gallatin, KY 22 41 19 19

Grant, KY 21 40 19 20

Hamilton, OH 23 41 18 19

Kenton, KY 22 41 18 19
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Ohio, IN 22 39 19 19

Pendleton, KY 21 40 19 20

Warren, OH 24 39 19 18

Adams, OH 22 39 20 19

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

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.

-Source: OKI web page, http://www.oki.org/

The Ohio portion of this area's ozone nonattainment area consists of the following Ohio

counties:

-Butler, Clermont, Hamilton, Warren, Clinton

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.

6.5.4.3 Cleveland-Akron-Lorain Area

Discussion:

There are violating monitors in Cuyahoga and Summit Counties. EPA is modifying the

Ohio EPA Option 2 recommendation to include Cuyahoga, Lake, Lorain, Medina,

Summit , and Portage Counties, and Ashtabula Township in Ashtabula County in the

Cleveland-Akron-Lorain nonattainment area. These counties are all in the ozone

nonattainment area, which will facilitate planning for both standards.

In the June 2004 letters from EPA to the States responding to their designation

recommendations, EPA proposed the designation of a number of counties primarily

because of high pollutant emissions from power plants. Most of these plants were

located in nearby counties adjacent to the metropolitan area (as defined either by the 1999

or 2003 OMB metropolitan area definitions). EPA suggested that a State could provide a

partial county boundary that would extend to the relevant power plant to include it in the

nonattainment area.
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A number of states responded to this suggestion with a series of connected townships or

other unique boundaries. Some states also suggested an alternative approach in which

partial county areas for power plants in some cases could be small “free-standing”

boundaries that are considered part of the nearby nonattainment area. In this way, it

would not be necessary to include additional townships or other minor civil divisions

comprising an odd-shaped “land connector” extending from the main part of the

nonattainment area to the power plant.

After considering these comments from the States, EPA agrees that such an approach is

preferable in cases where a partial county nonattainment boundary has not already been

established for that source (e.g. partial county boundaries recently established for 8-hour

ozone nonattainment areas). For purposes of consistency, EPA has decided that freestanding portions of nonattainment areas should be based on a pre-existing boundary for

a minor civil division (such as a township or tax district) or other boundary defined for

governmental use (such as a census block group or census tract). Accordingly, this kind

of partial county boundary should not be defined simply as the boundary of the facility.

Therefore, Ashtabula Township in Ashtabula County is a partial county area included in

the Cleveland-Akron-Lorain nonattainment area.

The State of Ohio submitted information on August 30, 2004, further supporting its

recommendation that Geauga County has low emissions and should not be included in

the nonattainment area. EPA agrees with this recommendation. EPA is also designating

most of Ashtabula County as nonattainment, with the exception of Ashtabula Township,

which contains the Ashtabula power plant and a significant fraction of the population of

Ashtabula County.

There are four counties adjacent to this metropolitan area that are not a part of another

metropolitan area. These are Erie, Huron, Ashland and Wayne Counties. Emissions are

relatively low for these counties.

Because emissions are relatively low for Ashland, Erie, Huron, and Wayne Counties, and

no other factor warranted designating these counties nonattainment, the following data

summaries for factors 3 through 9 do not address these counties.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emissions score

Ashtabula 14,985 16,470 870 1,098 9.7

Cuyahoga 15,440 52,547 3,126 1,808 28.0

Geauga 624 3,985 472 648 3.6
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Lake 53,219 24,531 1,074 1,570 16.2

Lorain 35,677 31,826 1,212 2,007 17.1

Medina 527 7,132 526 788 4.6

Portage 1,643 9,120 712 794 6.0

Summit 16,264 27,641 1,511 1,066 14.8

Ashland 825 3,460 214 663 2.4

Crawford, PA 1,231 8,034 413 772 4.4

Erie 1,341 7,327 447 635 11.8

Huron 557 3,828 242 697 2.6

Wayne 21,450 8,911 702 1,849 8.9

Urban increment:

Total mass= 7.1 μg/m3

13% sulfates; 34% nitrates; 42% carbon; 11% crustal.

Urban site=390350060

Rural site=MKGO1 (M.K. Goddard)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Cuyahoga 18.3 μg/m3

Lake 13.4 μg/m3

Lorain 13.9 μg/m3

Portage 14.2 μg/m3

Summit 16.6 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2003 Population Population Density

Ashtabula 102,515 146
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Cuyahoga 1,379,049 3,011

Geauga 92,980 230

Lake 229,004 1,004

Lorain 288,360 585

Medina 158,439 375

Portage 153,886 313

Summit 546,381 1,323

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Ashtabula 11,106 24 1,107

Cuyahoga 49,985 8 11,461

Geauga 24,452 55 901

Lake 42,894 37 1,833

Lorain 40,464 30 2,514

Medina 37,343 49 1,622

Portage 34,001 44 1,796

Summit 51,921 20 5,141

Factor 5. Expected growth:

County Percent growth 1990-2000

Ashtabula 3.0

Cuyahoga -1.0

Geauga 12.0

Lake 6.0

Lorain 5.0

Medina 23.0
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Portage 7.0

Summit 5.0

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Ashtabula 24 40 20 15

Cuyahoga 21 45 16 18

Geauga 23 41 20 16

Lake 22 43 18 17

Lorain 21 45 16 18

Medina 21 45 16 18

Portage 25 40 19 16

Summit 23 42 17 17

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

The Northeast Ohio Areawide Coordinating Agency (NOACA) is the Metropolitan

Planning Organization (MPO) for Cuyahoga, Geauga, Lake (OH), Lorain, and Medina

Counties.

-source: NOACA web page, http://www.noaca.org/

The area's ozone nonattainment area consists of the following counties:

-Ashtabula, Cuyahoga, Geauga, Lake, Lorain, Medina, Portage, and Summit

Factor 9. Level of control of emission sources:

Although the State has indicated that the power plant located in Ashtabula County has

reduced its NOX and SO2 emissions, EPA does not have information as to the

permanence or federal enforceability of those reductions, nor did the State indicate what
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portion of these emission reductions occurred after the 2001 date for which EPA’s

emissions data base applies.

6.5.4.4 Columbus Area

Discussion:

Franklin County contains a violating monitor. There are no other monitors in the

metropolitan area. Ohio EPA's Option 2 recommendation was to designate Delaware,

Fairfield, Franklin, and Licking Counties as nonattainment. EPA is including these

counties as well as Franklin Township in Coshocton County in the Columbus

nonattainment area. Pickaway and Madison Counties are excluded from the

nonattainment area. These two counties have the lowest composite emissions scores in

the metropolitan area. Pickaway County was not included as part of the ozone

nonattainment area, and Madison County was included in the ozone nonattainment area

because it contained a monitored violation of the ozone standard. These two counties

also have the lowest population, population density and vehicle miles traveled in the

metropolitan area. There are eleven counties adjacent to the metropolitan area that are

not included in another metropolitan area. Most of these counties have relatively low

emissions and do not warrant further discussion. The exception is Coshocton County,

which has significant emissions, principally from the Conesville power plant located in

Franklin Township. EPA believes that these emissions are contributing to the violation in

the Columbus Metropolitan Area. By designating Franklin Township in Coshocton

County as nonattainment, these emissions are being captured.

In the June 2004 letters from EPA to the States responding to their designation

recommendations, EPA proposed the designation of a number of counties primarily

because of high pollutant emissions from power plants. Most of these plants were

located in nearby counties adjacent to the metropolitan area (as defined either by the 1999

or 2003 OMB metropolitan area definitions). EPA suggested that a State could provide a

partial county boundary that would extend to the relevant power plant to include it in the

nonattainment area.

A number of states responded to this suggestion with a series of connected townships or

other unique boundaries. Some states also suggested an alternative approach in which

partial county areas for power plants in some cases could be small “free-standing”

boundaries that are considered part of the nearby nonattainment area. In this way, it

would not be necessary to include additional townships or other minor civil divisions

comprising an odd-shaped “land connector” extending from the main part of the

nonattainment area to the power plant.

After considering these comments from the States, EPA agrees that such an approach is

preferable in cases where a partial county nonattainment boundary has not already been

established for that source (e.g. partial county boundaries recently established for 8-hour

ozone nonattainment areas). For purposes of consistency, EPA has decided that freestanding portions of nonattainment areas should be based on a pre-existing boundary for

a minor civil division (such as a township or tax district) or other boundary defined for
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governmental use (such as a census block group or census tract). Accordingly, this kind

of partial county boundary should not be defined simply as the boundary of the facility.

Therefore, Franklin Township in Coshocton County is a partial county area included in

the Columbus nonattainment area.

Because emissions are relatively low for the counties adjacent to the metropolitan area

other than Coshocton County, and no other factor warranted designating these counties

nonattainment, the following data summaries for factors 3 through 9 do not address these

counties.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emissions score

Delaware 676 6,088 573 1,277 11.2

Fairfield 1,301 6,556 507 1,098 10.4

Franklin 6,435 41,541 2,084 2,098 48.2

Licking 1,054 7,815 909 1,701 17.1

Madison 233 3,106 259 1,033 5.2

Pickaway 9,854 5,971 363 1,282 7.9

Champaign 383 1,757 180 602 3.5

Coshocton 97,412 24,560 1,385 3,733 30.9

Fayette 309 2,136 204 669 4.0

Hocking 408 2,161 104 154 2.4

Knox 302 2,225 258 657 4.9

Marion 675 3,896 273 909 5.7

Morrow 291 2,434 157 532 3.4

Muskingum 1,908 5,595 363 656 7.8

Perry 327 2,079 133 326 2.9

Ross 31,103 8,000 423 910 9.6
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Union 377 2,202 246 897 4.7

Urban increment:

Total mass= 2.1 μg/m3

0% sulfates; 27% nitrates; 73% carbon; 0% crustal.

Urban site=390171004;

Rural site=LIVO1 (Livonia)

The Conesville Power Plant in Franklin Township represents approximately 99% SO2,

90% NOX, 78% Carbon and 87% Crustal emissions for Coshocton County. Therefore,

designating Franklin Township as nonattainment will capture the bulk of Coshocton

County’s emissions.

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Franklin 16.7 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Delaware 125,399 283

Fairfield 129,161 255

Franklin 1,086,814 2013

Licking 148,731 216

Madison 40,365 87

Pickaway 53,437 106

Coshocton 36,836 65

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Delaware 32,350 56 1,099

Fairfield 31,533 52 1,064
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Franklin 24,992 5 10,081

Licking 25,636 36 1,474

Madison 8,378 47 619

Pickaway 10,498 48 545

Coshocton 843 5 308

Factor 5. Expected growth

County Percent growth 1990-2000

Delaware 64

Fairfield 19

Franklin 11

Licking 13

Madison 8

Pickaway 9

Coshocton 3

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Delaware 24 35 23 19

Fairfield 24 34 23 19

Franklin 24 33 24 20

Licking 24 35 23 19

Madison 24 34 23 19

Pickaway 24 33 24 19

Coshocton 24 42 18 16
6-315

Muskingum 24 36 23 18

Perry 24 35 23 19

Ross 24 34 23 19

Union 24 34 23 19

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

The Mid-Ohio Regional Planning Commission (MORPC) is the Metropolitan Planning

Organization (MPO) for the Columbus, OH area.

Source: MORPC web page, http://www.morpc.org/MORPC.htm

The area's ozone nonattainment area consists of the following counties:

-Delaware, Franklin, Licking, Fairfield, Madison, and Knox

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.

6.5.4.5 Dayton-Springfield Area

Discussion:

There is a violating monitor in Montgomery County. EPA agrees with the Ohio EPA

Option 2 to include Clark, Greene, and Montgomery Counties in the Dayton-Springfield

nonattainment area. The majority of emissions and population are captured

notwithstanding the exclusion of Miami County, which has limited emissions and

population. Miami County is also lower in terms of population density and VMT in the

metropolitan area.

There are six counties adjacent to the metropolitan area and not included in another

metropolitan area. Emissions are relatively low for these counties, and no other factor

warranted designating these counties nonattainment. Therefore the following data

summaries for factors 3 through 9 do not address these counties.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:
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County SOx NOx Carbon Crustal Composite

emissions score

Clark 544 5,691 395 1,024 16.1

Greene 1,895 8,841 389 1,064 17.9

Miami 478 4,116 337 972 13.2

Montgomery 11,214 24,177 1,190 1,210 52.8

Champaign 383 1,757 180 602 6.8

Darke 551 3,174 381 1,316 14.0

Preble 428 2,765 228 721 8.9

Clinton 375 2,490 193 583 7.7

Fayette 309 2,136 204 669 7.8

Shelby 803 3,468 225 670 9.3

Urban increment:

Total mass= 2.1 μg/m3:

0% sulfates; 27% nitrates; 73% carbon; 0% crustal.

Urban site=390171004;

Rural site=LIVO1 (Livonia)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Clark 14.7 μg/m3

Greene 9.5 μg/m3

Montgomery 15.2 μg/m3

Preble 13.5 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density
6-317

Clark 143,416 359

Greene 149,964 361

Miami 99,596 245

Montgomery 554,470 1200

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Clark 14,604 22 1,483

Greene 27,963 38 1,299

Miami 13,764 28 850

Montgomery 31,453 12 5,668

Factor 5. Expected growth

County Percent growth 1990-2000

Clark -2

Greene 8

Miami 6

Montgomery -3

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Clark 25 36 21 18

Greene 25 36 21 18

Miami 25 38 20 17

Montgomery 25 38 20 17

Factor 7. Geography/topography:
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There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

The Miami Valley Regional Planning Commission (MVRPC) is the Metropolitan

Planning Organization (MPO) for the following counties: Greene, Miami, Montgomery,

and portions of Warren.

-Source: MVRPC website, http://www.mvrpc.org/index.htm

The area's ozone nonattainment area consists of the following counties:

-Clark, Greene, Miami, and Montgomery

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.

6.5.4.6 Huntington-Ashland Area

Discussion:

There are monitors showing violations of the standard in Scioto and Lawrence Counties.

Therefore, EPA agrees with Ohio’s Option 2 recommendation to designate these counties

nonattainment. We are also including Monroe and Sprigg Townships in Adams county

and Cheshire Township in Gallia County in this nonattainment area. Lawrence County is

the only county in the Ohio portion of the metropolitan area. Aside from Scioto County,

there are four counties in Ohio adjacent to the metropolitan area. These are Adams, Pike,

Jackson and Gallia Counties. Adams County contains the DP&L Killen Generating

Station and the DP&L J.M. Stuart Generating Station. Gallia contains the Ohio Power

Gavin power plant and Ohio Valley Electric Corporation Kyger Creek power plant. The

townships listed for Adams and Gallia counties are included to capture the significant

emissions from these plants which are contributing to violations.

In the June 2004 letters from EPA to the States responding to their designation

recommendations, EPA proposed the designation of a number of counties primarily

because of high pollutant emissions from power plants. Most of these plants were

located in nearby counties adjacent to the metropolitan area (as defined either by the 1999

or 2003 OMB metropolitan area definitions). EPA suggested that a State could provide a

partial county boundary that would extend to the relevant power plant to include it in the

nonattainment area.

A number of states responded to this suggestion with a series of connected townships or

other unique boundaries. Some states also suggested an alternative approach in which

partial county areas for power plants in some cases could be small “free-standing”
6-319

boundaries that are considered part of the nearby nonattainment area. In this way, it

would not be necessary to include additional townships or other minor civil divisions

comprising an odd-shaped “land connector” extending from the main part of the

nonattainment area to the power plant.

After considering these comments from the States, EPA agrees that such an approach is

preferable in cases where a partial county nonattainment boundary has not already been

established for that source (e.g. partial county boundaries recently established for 8-hour

ozone nonattainment areas). For purposes of consistency, EPA has decided that freestanding portions of nonattainment areas should be based on a pre-existing boundary for

a minor civil division (such as a township or tax district) or other boundary defined for

governmental use (such as a census block group or census tract). Accordingly, this kind

of partial county boundary should not be defined simply as the boundary of the facility.

Therefore, Monroe and Sprigg Townships in Adams county and Cheshire Township in

Gallia County are partial county areas included in the Hunting-Ashland nonattainment

area.

Emissions are relatively low for Pike and Jackson Counties, and no other factor

warranted designating these counties nonattainment. The following data summaries for

factors 3 through 9 do not address these counties.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emissions score

Boyd, KY 11,740 13,478 689 1,242 25.2

Cabell, WV 5,155 27,903 1,318 774 40.3

Carter, KY 237 2,615 242 249 6.8

Greenup, KY 2,519 4,336 295 160 9.5

Lawrence, OH 841 4,399 293 379 8.6

Wayne, WV 1,023 6,485 317 199 9.6

Adams, OH 125,136 52,992 1,435 3,973 102.4

Elliott, KY 115 393 114 46 3.1

Gallia, OH 164,984 61,079 2,171 6,238 141.4

Jackson, OH 461 1,320 164 219 4.7
6-320

Lawrence, KY 56,055 21,265 745 1,718 48.3

Lewis, KY 469 2,873 285 121 8.1

Lincoln, WV 67 1,314 143 108 4.0

Martin, KY 661 1,236 136 131 4.0

Mason, WV 70,053 31,327 899 2,162 60.0

Mingo, WV 281 2,842 191 217 5.5

Rowan, KY 313 1,691 204 123 5.7

Scioto, OH 2,790 5,566 400 559 12.5

Urban increment:

Total mass= 3.2 μg/m3:

10% sulfates; 6% nitrates; 84% carbon; 0% crustal.

Urban site=210190017;

Rural site=QUCI1 (Quaker City)

The DP&L Killen Generating Station and the DP&L J.M. Stuart Generating Station

represent approximately 99% of the SO2, 93% of the NOX, 88% of the carbonaceous

particles and 94% of the crustal emissions for Adams County. Designating Monroe and

Sprigg Townships as nonattainment will capture these emissions, and therefore the bulk

of the emissions for Adams County. The Ohio Power Gavin power plant and Ohio

Valley Electric Corporation Kyger Creek power plant represents approximately 99% of

the SO2, 97% of the NOX, 93% of the carbonaceous particles and 96% of the crustal

emissions for Gallia County. Designating Cheshire Township as nonattainment will

capture these emissions, and therefore the bulk of the emissions for Gallia County.

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Boyd, KY 15.0 μg/m3

Cabell, WV 16.6 μg/m3

Carter, KY 12.2 μg/m3

Lawrence 15.8 μg/m3

Scioto 17.2 μg/m3
6-321

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Lawrence, OH 62,172 137

Boyd, KY 49,603 310

Cabell, WV 95,266 338

Carter, KY 27,055 66

Greenup, KY 36,761 106

Wayne, WV 42,382 84

Adams 27,804 48

Gallia 31,301 67

Scioto 78,041 128

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Lawrence, OH 11,446 49 796

Boyd, KY 3,967 21 411

Cabell, WV 2,864 7 1,030

Carter, KY 2,088 20 665

Greenup, KY 5,743 40 264

Wayne, WV 8,203 52 377

Adams 2,578 23 283

Gallia 337 3 266

Scioto 1,333 5 633

Factor 5. Expected growth:
6-322

County Percent growth 1990-2000

Lawrence, OH 1

Boyd, KY -3

Cabell, WV 0

Carter, KY 10

Greenup, KY 0

Wayne, WV 3

Adams 8

Gallia 7

Scioto 9

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Lawrence, OH 22 39 20 19

Boyd, KY 21 38 21 19

Cabell, WV 22 39 20 20

Carter, KY 2 39 20 20

Greenup, KY 22 39 20 19

Wayne, WV 22 39 20 20

Adams 22 39 20 19

Gallia 22 39 20 20

Scioto 22 39 20 20

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.
6-323

Factor 8. Jurisdictional boundaries:

The KYOVA Interstate Planning Commission is the Metropolitan Planning Organization

(MPO) for Lawrence County, OH.

-Source: KYOVA website. http://www.state.wv.us/kyova/

There are no counties in the Ohio portion of the metropolitan area designated

nonattainment for the ozone standard.

Factor 9. Level of control of emission sources:

The state has indicated that selective catalytic reduction (SCR) equipment has been

installed on the DP&L Killen Generating Station and the DP&L J.M. Stuart Generating

Station in Adams County and on the Ohio Power Gavin power plant and the Ohio Valley

Electric Corporation Kyger Creek power plant in Gallia County. However, EPA does not

have information as to the permanence, federal enforceability, or magnitude of those

reductions. It is also unclear whether the NOX emission controls are operated on an

annual basis. The state is in the process of reviewing modeling protocols for SO2

scrubber installations at the DP&L Killen Generating Station and the DP&L J.M. Stuart

Generating Station. The scrubbers have not yet been installed, there is no current

requirement for installation of this equipment, and EPA has no information on when

these possible reductions might occur. Thus, EPA is not giving credit to these reductions

as part of its designations decisionmaking.

6.5.4.7 Parkersburg-Marietta Area

Discussion:

Only one county in Ohio, Washington County, is in the metropolitan area. This county

has a high level of emissions and contributes to violations in Wood County, West

Virginia. Washington County also has a significant fraction of the area's population.

Therefore, EPA is designating Washington County nonattainment as part of the

Parkersburg-Marietta nonattainment area.

There are five counties in Ohio adjacent to the metropolitan area, including Meigs,

Athens, Morgan, Noble and Monroe Counties. Emissions are relatively low for these

counties, and no other factor warranted designating these counties nonattainment. The

following data summaries for factors 3 through 9 do not address these counties.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal

Composite

emission score

Washington 173,312 37,020 2,415 6,711

82.2
6-324

Wood, WV 6,514 6,943 591 482

17.8

Athens 733 3,166 176 222

5.4

Jackson, WV 3,464 3,947 451 1,128

13.3

Meigs 375 2,244 147 145

4.4

Monroe 4,532 2,809 162 504

5.2

Morgan 81 558 88 122

2.5

Noble 144 1,622 87 127

2.7

Pleasants, WV 68,264 23,398 823 1,411

30.1

Ritchie, WV 118 713 97 63

2.8

Tyler, WV 176 1,233 122 126

3.6

Wirt, WV 19 206 46 36

1.3

Urban increment:

Total mass= 3.2 μg/m3:

10% sulfates; 6% nitrates; 84% carbon; 0% crustal.

Urban site=210190017;

Rural site=QUCI1 (Quaker City)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Wood, WV 16.0 μg/m3

Athens 12.5 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Washington 62,561 99

Wood, WV 87,306 238

Factor 4. Traffic and commuting patterns:
6-325

County Number Percent County VMT

(Thousands)

Washington 5,927 21 737

Wood, WV 3,316 9 911

Factor 5. Expected growth:

County Percent growth 1990-2000

Washington 2

Wood, WV 1

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Washington 22 37 19 21

Wood, WV 22 39 18 21

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

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.

-Source: WWW website, http://www.triplew.org/index.html

The area's ozone nonattainment area consists of the following counties:

-Washington County, OH, and Wood County, WV

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.
6-326

6.5.4.8 Steubenville-Weirton Area

Discussion:

The only Ohio county in the metropolitan area is Jefferson County. There is a monitor

violating the standard in Jefferson County. EPA agrees with Ohio and is including

Jefferson County in the Steubenville-Weirton nonattainment area. There is one county

adjacent to the metropolitan area in Ohio that is not part of another violating metropolitan

area, namely Harrison County. This county has a low composite emissions score as well

as having relatively low population and VMT for the area.

Because emissions are relatively low for Harrison County, and no other factor warranted

designating this county nonattainment, the following data summaries for factors 3

through 9 do not address this county.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emission score

Brooke, WV 1,663 2,500 191 277

3.7

Hancock, WV 1,982 4,961 1,243 1,747

18.7

Jefferson 217,794 61,402 2,723 7,529

77.6

Harrison 258 712 70 116

1.3

Urban increment:

Total mass= 4.2 μg/m3:

11% sulfates; 30% nitrates; 49% carbon; 10% crustal.

Urban site=390990014;

Rural site=MKGO1 (M.K. Goddard)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Brooke, WV 16.8 μg/m3

Hancock, WV 17.4 μg/m3

Jefferson 17.8 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:
6-327

County 2002 Population Population Density

Brooke, WV 25,179 283

Hancock, WV 32,082 387

Jefferson 72,402 177

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Brooke, WV 2,548 24 313

Hancock, WV 4,029 28 212

Jefferson 3,161 11 741

Factor 5. Expected growth:

County Percent growth 1990-2000

Brooke, WV -6

Hancock, WV -7

Jefferson -8

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Brooke, WV 29 36 19 16

Hancock, WV 29 36 19 16

Jefferson 28 37 19 16

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.
6-328

Factor 8. Jurisdictional boundaries:

The Brooke-Hancock-Jefferson Metropolitan Planning Commission (BHJMPC) is the

Metropolitan Planning Organization (MPO) for Jefferson County, OH.

-Source: BHJMPC website, http://www.bhjmpc.org/

The Ohio portion of this ozone nonattainment area consists of the following county:

-Jefferson

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.

6.5.4.9 Toledo Area

Discussion:

There is a violating monitor in Lucas County. EPA agrees with the Ohio EPA’s Option 2

recommendation and is designating Lucas and Wood Counties as the Toledo

nonattainment area. Fulton County is also in the Metropolitan area but was excluded

upon review of the nine factors. Fulton County has lower emissions, population,

population density, and VMT in the Metropolitan area. Fulton County was also excluded

from the ozone nonattainment area. There are several counties adjacent to the

metropolitan area and in Ohio, including Hancock, Henry, Ottawa, Putnam, Sandusky,

Seneca, and Williams Counties. These counties have lower composite emissions scores

and are also lower in the other factors including population and VMT.

Thus, no other factor warranted designating these counties nonattainment. The following

data summaries for factors 3 through 9 do not address these counties.

Monroe County, Michigan, has a design value of 15.1 μg/m3, but this county is part of

the Detroit Metropolitan Area. EPA is designating this county as part of the Detroit

nonattainment area.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emission score

Fulton 878 5,105 336 692

12.0

Lucas 31,000 36,975 1,370 1,702

69.2

Wood 1,410 8,822 466 1,413

18.8
6-329

Hancock 567 4,351 342 1,036

11.1

Henry 3,139 2,547 185 662

6.3

Hillsdale, MI 1,286 3,270 245 812

8.2

Ottawa 1,544 5,031 403 687

13.0

Putnam 306 2,749 237 935

7.4

Sandusky 2,937 8,288 300 1,170

15.4

Seneca 826 4,575 281 951

10.4

Williams 469 3,600 196 634

7.8

Urban increment:

Total mass= 4.8 μg/m3:

0% sulfates; 64% nitrates; 36% carbon; 0% crustal.

Urban site=390950026;

Rural site=QUCI1 (Quaker City)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Lucas 15.1 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Fulton 42,573 105

Lucas 453,506 1334

Wood 122,387 198

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Fulton 5,825 28 672
6-330

Lucas 19,011 9 4,324

Wood 19,773 32 1,400

Factor 5. Expected growth:

County Percent growth 1990-2000

Fulton 9

Lucas -2

Wood 7

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Fulton 25 41 16 18

Lucas 24 41 16 19

Wood 24 41 16 18

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

The Toledo Metropolitan Area Council of Governments (TMACOG) is the Metropolitan

Planning Organization (MPO) for Fulton, Lucas, Ottawa, Sandusky, and Wood Counties

in Ohio.

-Source: TMACOG web page, http://www.tmacog.org/

This area's ozone nonattainment area consists of the following counties:

-Lucas and Wood

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.
6-331

6.5.4.10 Wheeling Area

Discussion:

The only Ohio county in the metropolitan area is Belmont County. This county contains

higher emissions due in part to the R.E. Burger power plant. This county was also

included as part of the ozone nonattainment area and contains the largest county

population in the metropolitan area. There are four Ohio counties adjacent to the

metropolitan area, namely Guernsey, Harrison, Monroe, and Noble Counties. These

counties are excluded due to lower emissions, population and VMT.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emission score

Belmont, OH 51,374 13,036 734 1,667 29.5

Ohio, WV 514 3,609 192 135 5.5

Marshall, WV 113,921 44,521 1,319 3,417 65.0

Greene, PA 217,794 61,402 2,723 7,529 99.2

Guernsey, OH 1,164 5,643 229 261 7.3

Harrison, OH 258 712 70 116 1.8

Monroe, OH 4,532 2,809 162 504 5.5

Noble, OH 144 1,622 87 127 2.5

Wetzel, WV 698 4,323 160 79 5.2

Urban increment:

Total mass= 5.7 μg/m3:

27% sulfates; 24% nitrates; 46% carbon; 3% crustal.

Urban site=421290008;

Rural site=DOSO1 (Dolly Sods /Otter Creek Wilderness)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Ohio, WV 15.2 μg/m3
6-332

Marshall, WV 15.7 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Belmont, OH 69,448 129

Ohio, WV 46,126 435

Marshall, WV 34,898 114

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Belmont, OH 5,667 20 1,066

Ohio, WV 2,964 15 437

Marshall, WV 5,233 37 233

Factor 5. Expected growth:

County Percent growth 1990-2000

Belmont, OH -1

Ohio, WV -7

Marshall, WV -5

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Belmont, OH 28 37 19 16

Ohio, WV 29 36 19 16

Marshall, WV 28 36 19 16

Factor 7. Geography/topography:
6-333

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

The Bel-O-Mar Regional Council and Interstate Planning Commission is the

Metropolitan Planning Organization (MPO) for Belmont County, OH.

-Source: Bel-O-Mar Regional Council website, http://www.belomar.org/

The Ohio portion of this area's ozone nonattainment area consists of the following county

in Ohio: -Belmont

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.

6.5.4.11 Youngstown-Warren Area

Discussion:

EPA agrees with the Ohio EPA’s Option 2 recommendation to include Columbiana,

Mahoning and Trumbull Counties as nonattainment. These counties all have significant

emissions contributing to the violations in Mahoning County. There are no adjacent

counties to this metropolitan area in Ohio that are not a part of another violating

metropolitan area.

Ohio’s submittal of September 1, 2004, urges EPA to designate Columbiana County as

attainment. However, EPA finds that this county contributes a significant percentage of

the emissions in the Youngstown-Warren Area. In addition, this county is surrounded by

monitors showing violations, which suggests that Columbiana County (which has no

monitoring data) may be experiencing concentrations above the standard.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal composite

emission score

Columbiana 1,291 5,825 442 696 15.9

Mahoning 3,511 12,210 920 804 31.2

Trumbull 30,327 19,010 1,217 1,365 52.9

Mercer, PA 874 7,459 412 760 16.7
6-334

Crawford, PA 1,231 8,034 413 772 17.3

Lawrence, PA 35,620 13,065 681 1,833 41.2

Urban increment:

Total mass= 4.2 μg/m3:

11% sulfates; 30% nitrates; 49% carbon; 10% crustal.

Urban site=390990014;

Rural site=MKGO1 (M.K. Goddard)

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Mahoning 15.2 μg/m3

Trumbull 15.0 μg/m3

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2002 Population Population Density

Columbiana 111,806 210

Mahoning 253,308 610

Trumbull 223,518 363

Factor 4. Traffic and commuting patterns:

County Number Percent County VMT

(Thousands)

Columbiana 9,090 18 928

Mahoning 22,894 21 2,576

Trumbull 12,347 13 2,108

Factor 5. Expected growth:

County Percent growth 1990-2000
6-335

Columbiana 4

Mahoning -3

Trumbull -1

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Columbiana 27 39 18 17

Mahoning 25 39 21 15

Trumbull 25 38 22 15

Factor 7. Geography/topography:

There are no geographical features (mountain ranges, abrupt changes in elevation, etc.)

that affect this area. The State provided no information about geography/topography for

this area.

Factor 8. Jurisdictional boundaries:

The Eastgate Regional Council of Governments (Eastgate) is the Metropolitan Planning

Organization (MPO) for Mahoning and Trumbull Counties in Ohio.

-Source: Eastgate web page, http://www.eastgatecog.org/

The Ohio portion of this area's ozone nonattainment area consists of the following

counties:

-Columbiana, Mahoning, and Trumbull

Factor 9. Level of control of emission sources:

The State provided no information about the level of control of emission sources for this

area.
6-336

6.5.5 EPA 9-Factor Analyses for Wisconsin for Designation of

Nonattainment Areas for PM2.5

EPA is designating all Wisconsin counties as attainment/unclassifiable. The only area in

or near Wisconsin with a monitored violation is the Chicago-Gary-Kenosha Area.

Wisconsin did not provide a recommended list of designations in February 2004.

Therefore, EPA sent the State a letter on June 29, 2004, stating an intent to designate

Kenosha County nonattainment because this county is part of the Chicago-Gary-Kenosha

metropolitan area and thus was presumptively part of the Chicago-Gary-Kenosha

nonattainment area. Governor Doyle then sent EPA a letter on August 9, 2004,

recommending that Kenosha County be designated attainment. The following discussion

presents EPA’s rationale for its designations in the Wisconsin portion of the ChicagoGary-Kenosha Area.

6.5.5.1 Chicago-Gary-Kenosha Area

Discussion:

EPA reviewed the nine factors for the thirteen counties within the metropolitan area

including Kenosha County in Wisconsin as well as all counties adjacent to the

metropolitan area in order to determine the appropriate nonattainment area. There are

violating monitors in Cook County, Illinois and in Lake County, Indiana. Kenosha

County monitoring indicates that PM2.5 concentrations in the county are below the

standard. The counties in Illinois and Indiana that are being designated as nonattainment

include 90% of the metropolitan area emissions. Kenosha County emissions are

relatively low and will continue to decrease as federally enforceable SO2 and NOX

controls are installed at the Pleasant Prairie Power Plant operated by WE Energies.

Furthermore, prevailing winds in Kenosha County are predominantly away from the

violating monitors in the metropolitan area. Therefore, EPA agrees with Governor Jim

Doyle’s recommendation to designate Kenosha County as attainment/unclassifiable.

In Wisconsin, Racine and Walworth Counties are adjacent to the metropolitan area.

Emissions are relatively low for these counties, and no other factor warranted designating

these counties nonattainment. Therefore, the following data summaries for factors 3

through 9 do not address these counties.

Factor 1. Emissions in areas potentially included versus excluded from the

nonattainment area:

County SOx NOx Carbon Crustal Composite

emissions score

Cook 61,676 195,428 10,110 8,268 33.0

De Kalb 445 4,885 384 1,875 1.0

Du Page 2,990 29,479 1,731 1,229 4.9

Grundy 6,149 9,589 563 1,235 2.1
6-337

Kane 1,395 9,490 1,047 2,326 2.8

Kankakee 551 6,628 490 1,720 1.4

Kendall 292 2,941 265 961 0.7

Lake 14,223 24,488 2,092 1,777 6.7

Mc Henry 637 5,834 564 1,992 1.6

Will 80,847 37,518 1,447 4,120 11.7

Lake, IN 50,110 72,142 5,708 7,588 19.5

Porter, IN 21,601 41,315 2,702 5,587 9.2

Kenosha, WI 33,122 27,469 770 1,236 5.4

Boone 849 2,188 215 834 0.6

Ford 219 1,462 216 1,280 0.6

Iroquois 458 4,177 452 2,290 1.3

La Salle 2,140 13,984 845 3,352 2.5

Lee 3,978 4,793 345 1,722 1.3

Livingston 503 4,686 485 2,413 1.3

Ogle 672 4,985 335 1,536 1.1

Winnebago 1,100 10,496 656 1,405 1.9

Benton, IN 101 1,326 215 724 0.5

Berrien, IN 1,390 10,269 740 1,340 0.6

Jasper, IN 34,435 23,020 668 1,838 5.2

La Porte, IN 10,974 19,681 826 1,643 3.3

Newton, IN 89 1,321 160 642 0.4

Pulaski, IN 111 1,187 196 667 0.5

St Joseph, IN 2,850 13,690 1,482 1,825 4.0

Starke, IN 100 2,852 188 551 0.5

White, IN 188 2,495 292 1,185 0.8

Racine, WI 2,309 7,252 662 890 1.9

Walworth, WI 866 5,693 470 908 1.3

Urban increment:

Total mass= 3.6 μg/m3

25% sulfates; 8% nitrates; 65% carbon; 2% crustal.

Urban site= 170310076;
6-338

Rural site= BOND1 (Bondville)

The counties in Illinois and Indiana that are being designated as nonattainment include

90% of the metropolitan area emissions. Kenosha County emissions are relatively low

and will continue to decrease as federally enforceable SO2 and NOX controls are installed

at the Pleasant Prairie Power Plant operated by WE Energies. (See Factor 9.) When

controls are fully implemented in 2008, Kenosha County emissions are projected to drop

to 6,626 tons per year for SO2 and 11,727 tons per year for NOX, based on maximum

allowable emissions. The resulting composite emission score would drop from 5.4 to 2.7.

Factor 2. Air quality in potentially included versus excluded areas:

County 2001-2003 Design Value

Cook 17.3 μg/m3

Du Page 14.4 μg/m3

Kane 14.2 μg/m3

Lake 12.8 μg/m3

Mc Henry 12.7 μg/m3

Will 12.8 μg/m3

Lake, IN 17.7 μg/m3

Porter, IN 13.8 μg/m3

Kenosha, WI 11.7 μg/m3

La Porte 13.6 μg/m3

La Salle 14.1 μg/m3

Winnebago 13.6 μg/m3

St Joseph, IN 14.3 μg/m3

Berrien, MI 12.7 μg/m3

At 11.7 μg/m3, the design value for the Kenosha County monitor is well below the 15

μg/m3 standard, as is the design value for Lake County, Illinois, which is between the

Kenosha County monitor and the violating monitor in Cook County, Illinois.

Factor 3. Population density and degree of urbanization including commercial

development in included versus excluded areas:

County 2003 Population Population Density

Cook 5,377,507 5,684
6-339

De Kalb 91,561 144

Du Page 924,589 2,768

Grundy 38,839 92

Kane 443,041 850

Kankakee 104,657 154

Kendall 61,222 191

Lake 674,850 1,506

Mc Henry 277,710 460

Will 559,861 669

Lake, IN 487,016 980

Porter, IN 150,403 360

Kenosha, WI 154,433 566

Factor 4. Traffic and commuting patterns:

County County VMT Percent Number

Cook 44,107,000 12 274,167

De Kalb 729,000 31 13,894

Du Page 6,609,000 40 186,686

Grundy 530,000 46 8,431

Kane 841,000 43 82,968

Kankakee 889,000 19 9,122

Kendall 278,000 67 19,070

Lake 3,549,000 32 100,810

Mc Henry 792,000 47 62,415

Will 2,136,000 55 131,834

Lake, IN 5,012,000 25 52,922

Porter, IN 1,680,000 36 25,819

Kenosha, WI 1,228,000 28 20,506

Factor 5. Expected growth:

County Percent growth 1990-2000
6-340

Cook 5

De Kalb 14

Du Page 16

Grundy 16

Kane 27

Kankakee 8

Kendall 38

Lake 25

Mc Henry 42

Will 41

Lake, IN 2

Porter, IN 14

Kenosha, WI 17

Factor 6. Meteorology:

Average percent of wind direction by quadrant

County Northwest Southwest Southeast Northeast

Cook 26 37 16 21

De Kalb 27 34 19 21

Du Page 26 37 17 21

Grundy 26 36 17 21

Kane 26 35 18 21

Kankakee 25 38 17 19

Kendall 26 36 17 21

Lake 26 37 17 20

Mc Henry 28 32 19 20

Will 26 37 17 21

Lake, IN 25 38 17 19

Porter, IN 25 38 18 19

Kenosha, WI 28 35 18 20
6-341

Approximately 72% of the time, the prevailing wind direction in Kenosha County is

away from the violating monitors.

Factor 7: Geography/topography

The geography/topography analysis looks at physical features of the land that might have

an effect on the airshed, and therefore, the distribution of particulate matter over an area.

The State of Wisconsin has no features that significantly influenced EPA’s intended

nonattainment areas.

Factor 8: Jurisdictional boundaries

Factor 9: Level of control of emission sources

The Pleasant Prairie Power Plant operated by WE Energies accounts for approximately

97% of the SO2 and 78% of the NOX emissions in Kenosha County. The facility is in the

process of installing control equipment on its two coal-fired boilers which will result in

reductions in excess of 80% for SO2 and 70% for NOX. Specifically, the facility is

implementing the following federally enforceable controls1:

• Selective catalytic reduction (SCR) was installed in 2003 on one coal-fired boiler, to meet

an allowable rate of 0.100 lb/MMBtu on a 30 day rolling average. This results in over a

70% reduction in NOX, comparing 2001 actual emissions to allowable emissions as of

January 30, 2004.

• Contracts have been awarded for flue gas desulfurization (FGD) to be installed for SO2

control on both of the facility’s coal-fired boilers. Each unit will be subject to an

allowable rate of 0.100 lb/MMBtu on a 30 day rolling average, resulting in greater than

an 80% reduction comparing 2001 actual emissions to allowable emissions as of January

30, 2007 for one unit and January 30, 2008 for the other.

A contract is being finalized to install SCR on the remaining coal-fired boiler. NOX

emissions will be controlled to meet an allowable rate of 0.10 lb/MMBtu on a 30 day

rolling average. This results in greater than 70% reductions when comparing 2001 actual

emissions to allowable emissions as of January 30, 2007.

 1

This level of control is reflective of requirements found in a consent decree that is not

yet final but is under review by a circuit court judge. The level of control is reflected in a

federally enforceable permit.
6-342

6.7 Region 7 Nonattainment Areas

6.7.1 EPA 9-Factor Analyses for Missouri for Designation of PM2.5

Nonattainment Areas

Recommendations:

MO-IL CMSA Area EPA Recommendation State Recommendation

Missouri Nonattaining full counties:

Franklin

Jefferson

St. Charles

St. Louis

St. Louis City

Nonattaining full counties:

Franklin

Jefferson

St. Charles

St. Louis

St. Louis City

In Missouri the MO-IL St. Louis CMSA counties include Franklin, Jefferson, Lincoln, St.

Charles, St. Louis, St. Louis City, and Warren Counties.

Analysis

The following is a brief summary of the 9-factor analysis for the Missouri portion of the

MO-IL St. Louis C/MSA. Missouri counties that are in the CMSA are in bold; other

counties are adjacent to the C/MSA counties.

Factor 1: Emissions

For this factor, EPA Region 7 looked at primary PM2.5, SO2, NOx, carbon, and crustal

PM2.5 emissions. An emissions score was developed for each county to serve as an

indicator of the local PM2.5 contribution for the CMSA. The emissions score was

derived as follows:

Emissions Score = [(county SO2 tons/CMSA SO2 tons)*(% sulfate of urban excess

PM2.5)]

+ [(county NOx tons/CMSA NOx tons)*(% nitrate of urban excess PM2.5)]

+ [(county carbon tons/CMSA carbon tons)*(% carbon of urban excess PM2.5)]

+ [(county crustal PM tons/CMSA crustal PM tons)*(% crustal of urban excess PM2.5)]

The emissions score incorporated an urban excess factor to evaluate the local-scale

contribution for the pollutants listed below. This excess factor (local-scale contribution)

was determined by comparing speciated pollutants measurements between the St. Louis

(urban) monitor at Blair Street with the rural monitor at Mingo located in Stoddard

County approximately 120 miles SSE of St. Louis. The local-scale contribution for each

pollutant category is as follows:
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Urban Excess (mass) – 6.2 ug/m3

Nitrates - (29%)

Sulfates - (8%)

Total Carbon Mass - (58%)

Crustal Material - (5%)

By evaluating the speciation data between these two monitoring sites, one is able to

differentiate between regional and local source influences. Regional influences are seen

predominantly in the summertime with sulfate sources (power plants), while during the

fall and winter seasons, higher levels of total carbon and nitrates are seen from local

sources.

The emissions score for all 12 counties (Missouri and Illinois) within MO-IL C/MSA add

to 100. Counties adjacent to the C/MSA are also calculated an emissions score so that

emissions from those counties can be compared to the CMSA counties.

The following table shows total emissions (in tons/year) and emission scores for Missouri

counties that are included in the MO-IL St. Louis C/MSA and for those that are adjacent

to the CMSA. (Date source: 2001 NEI)

County direct

PM2.5

(tons/yr)

SO2

(tons/yr)

NOx

(tons/yr)

Carbon

PM2.5

(tons/yr)

Crustal/

other

direct

PM2.5

(tons/yr)

Emission

Score

Cum

Emission

Score

St. Louis, MO 6,689 30,400 53,358 3,456 2,897 27.4 27.4

St. Louis City,

MO

2,424 14,647 27,193 1,214 958 11.0 55.2

Jefferson, MO 4,870 52,671 13,612 1,160 3,291 10.4 65.6

St. Charles, MO 3,424 40,596 25,793 896 2,415 10.2 75.8

Franklin, MO 4,066 45,216 15,482 918 2,864 9.1 84.9

Lincoln, MO 1,650 221 2,935 273 1,358 2.1 93.8

Warren, MO 889 324 1,803 205 674 1.5 98.9

Crawford, MO 590 110 2,199 183 396 1.4

Gasconade, MO 533 248 1,727 132 393 1.0

Montgomery, MO 879 364 1,740 145 719 1.2

Pike, MO 1,156 15,206 10,931 206 773 3.3

St. Francois, MO 1,212 697 4,204 328 825 2.5

* Ste. Genevieve,

MO

1,308 9,205 18,027 255 940 2.7 to 4.2

Washington, MO 467 152 1,161 137 322 1.0

* -- Emissions in Ste. Genevieve County were adjusted to account for industrial growth

from new permits and PSD applications received by the state of Missouri. This growth

resulted in the cumulative emission score changing from 2.7 to 4.2.

A natural break was observed for Missouri counties with an emission score 9.1 and

above. In the case of the MO-IL, the natural break CMSA county is Franklin Co., MO
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(Emission Score = 9.1). Applied to Missouri, this process identifies St. Louis, St. Louis

City, Jefferson, St. Charles, and Franklin counties in MO as candidates for a PM2.5

nonattainment designation (i.e., counties with emission scores >= 9.1), and, therefore,

requiring further analysis of the remaining factors is required (see below).

Crawford, Gasconade, Montgomery, Pike, St. Francois, Ste. Genevieve, and Washington

counties in Missouri are dropped from further analysis because (1) none of these counties

contain violating PM2.5 monitors, (2) none were recommended for a nonattainment

designation by the state, and (3) al have emission scores significantly below < 9.1. The

next closest county is Ste. Genevieve with an emission score of 4.2 based upon projected

emissions from industrial growth. NOx emissions increased for St. Genevieve from

industrial growth by 12,000 tons/year, while SO2 emissions increased by 4,000 tons/year.

Factor 2: Air Quality

County 2001-2003 design value

(PM2.5 in _g/m3)

St. Louis City, MO 15.2

Jefferson, MO 14.5

St. Charles, MO 14.3

St. Louis, MO 14.0

Based on the analysis for this factor, only one county, St. Louis City, shows a violation of

the annual PM2.5 standard. The violating area (St. Louis City) must have a

nonattainment designation. However, this factor alone is not sufficient to eliminate the

other counties as candidates for nonattainment status.

Factor 3: Population Density and Urbanization

County 2002

Population

(people)

2002 Pop

Density

(pop/sq mi)

St. Louis, MO 1,018,102 2,004

St. Louis City, MO 338,353 5,457

St. Charles, MO 303,030 540

Jefferson, MO 203,993 310

Franklin, MO 95,890 104

Factors 3-5 correlate very well with mobile source emissions, population and commuting

activities. An evaluation of these factors and Vehicles Miles Traveled (VMT) data

support the county emission scores in Factor 1. The national approach of utilizing

emission scores outlined in Factor 1 supported the recommendations made by the state.

Factor 4: Traffic and commuting patterns

County 2002 VMT

(1000 miles)

VMT Growth1

(1000 miles)

VMT % Change2

St. Louis, MO 11,553 3,280 24

St. Louis City, MO 4,178 1,719 41
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St. Charles, MO 2,738 577 21

Jefferson, MO 2,511 322 13

Franklin, MO 1,391 -263 -19 1

 2002 to 2010

2

 2002 to 2010 (as percentage of 2002 population)

Factor 5: Expected growth

County 2002 Population

(people)

Population

Growth1

(people)

% Change2

St. Louis, MO 1,018,102 22,786 2

St. Louis City, MO 338,353 -48,496 -12

St. Charles, MO 303,030 70,976 33

Jefferson, MO 203,993 26,719 16

Franklin, MO 95,890 104 16 1

 2002 to 2010

2

 Estimated change in population growth, 2002 to 2010 (as a percentage of 2002 population)

Factors 6-9 did not significantly influence the designation process.

Factor 6: Meteorology

An evaluation conducted by Region 7 included trajectory cluster analysis using sulfate,

nitrate, and organic carbon PM2.5 speciation measurements for the Blair Street site in St.

Louis. This analysis generates back trajectories from the HYSPLIT model to

characterize meteorological events for 8 specific clusters. High nitrate events occurred

from trajectories originating from the North – Northwest, which agrees with the

atmospheric chemistry for nitrate formation that occurs during fall/winter cooling

periods. High sulfate events occurred during the summer with trajectories occurring from

the Ohio River Valley or upper Mississippi River Valley.

Factor 7: Geography/topography

The Missouri counties of the St. Louis MO-IL CMSA counties do not have any

geographical or topographical boundaries limiting transport across this airshed. The only

observation noted in our review was the noticeable gradient of PM2.5 measurements as

you go from east to west possibly indicating a more significant source of PM2.5 sources

from the East or Illinois side of the River. The critical monitor is located in Madison

County, Illinois with a 2001-2004 design value of 17.5 _g/m3. As you move from East to

West, the ambient levels drop to 14 _g/m3.

Factor 8: Jurisdictional boundaries

Jurisdictional boundaries did not play a role in determining nonattainment boundaries.

Areas designated as 8-hour ozone nonattainment areas are also important boundaries for

state air quality planning. Franklin, Jefferson, St. Charles, St. Louis, and St. Louis City

were included in the nonattainment area associated with the St. Louis 8-hour ozone

nonattainment area. A goal in designating PM2.5 nonattainment areas is to achieve a
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degree of consistency with ozone NA areas. Comparison of ozone areas with potential

PM2.5 NA areas, therefore, gives added weight to designation of the above counties.

Factor 9: Level of control of emission sources

A review of all the factors as well as the recommendations and supporting documentation

from the state of Missouri did not identify any additional counties that should be

excluded or included in the St. Louis PM2.5 nonattainment area. Based upon this review

and the methodology established by the PM2.5 Review Team consisting of members

from Regions 1-5 and 7-9 as well as representatives from the Office of Air Quality

Planning and Standards, the following Missouri counties are recommended for

nonattainment for PM2.5 for the St. Louis Metropolitan Area:

St. Louis

St. Louis City

St. Charles

Jefferson

Franklin
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6.8 Region 8 Nonattainment Areas

6.8.1 EPA 9-Factor Analyses for Montana for the Designation of PM2.5

Nonattainment Areas

Based on air quality data for 2001-2003, the PM2.5 monitor at the Libby Courthouse

Annex is violating the annual PM2.5 standard. EPA utilized the 9 factors identified in

the April 1, 2003 “Designations for the Fine Particle National Ambient Air Quality

Standards” guidance to evaluate whether the surrounding rural counties around Lincoln,

MT should be included as part of the nonattainment area. However, due to the

topographical features and local meteorology within Lincoln County and more

specifically around the Libby, Montana vicinity, several of the 9 factors were not

significant for this particular nonattainment area when looking at adjacent counties to

Lincoln County, MT. Lincoln County is considered a rural county, according to EPA’s

April 1, 2003 “Designations for the Fine Particle National Ambient Air Quality

Standards” which defines a rural area as counties or areas not included in or adjacent to

urban areas (metropolitan statistical areas (MSA). The adjacent areas to Lincoln County

are the Canadian border to the North, Boundary and Bonner County, Idaho to the West,

Sanders County, MT to the South, and Flathead County, MT to the East. Lincoln County

contains a violating monitor located in the town of Libby. The Lincoln County PM2.5

nonattainment issue is unique in that the area of impact is localized within and around the

vicinity of the town of Libby due to topographical features and meteorology in the area

impacted by emissions.

Montana’s recommendation identifying the PM2.5 nonattainment area included part of

Lincoln County (the town of Libby and vicinity). EPA initially responded to Montana’s

recommendation stating that EPA agreed with Montana’s recommended nonattainment

designation for Lincoln County but that EPA intended to modify Montana’s

recommended boundary for the nonattainment area to cover all of Lincoln County.

However, based upon supplemental information provided by Montana, EPA is

identifying the boundary of this PM2.5 nonattainment area to include a part of Lincoln

County as described further below.

The following is a brief summary of the 9 factor criteria for the Lincoln County, MT area

and surrounding counties. These analyses were based on existing available data. The

counties recommended as nonattainment are in bold.

Factor 1: Emissions in areas potentially included versus excluded from the

nonattainment area

For this factor, EPA looked at SO2, NOx, carbon and crustal PM2.5 emissions. A

weighted emissions score was applied to Lincoln County and the adjacent counties

reflecting the speciation profile of Lincoln County versus the adjacent counties. Counties

adjacent to the Lincoln County were assigned an emission score as a way to compare the

emissions from those counties against Lincoln County emissions. The following table

has the SO2, NOx, carbon, and crustal PM2.5 emissions and composite emission scores.
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This information is from the 2001 NEI. (The recommended nonattainment area is in

bold.)

County

SO2

(tons)

NOx

(tons)

Carbon

(tons)

Crustal

PM2.5

(tons)

Composite

Emission

Score

Lincoln 257 3286 862 275 100

Flathead 1919 6651 1788 1904 257

Bonner 313 5324 1411 730 159.5

Boundary 114 1886 1431 760 134.4

Sanders 328 4543 605 151 88.2

Since Lincoln County is considered to be a rural county as defined in EPA’s April 1,

2003 PM2.5 Designations Guidance and not a metropolitan statistical area, this factor did

not play a significant role in the decision making process. Also, due to the topographical

features and meteorology in Lincoln County (see factors 6 and 7 below) and more

specifically surrounding Libby, MT where the PM2.5 problem is, EPA feels the

surrounding counties emissions are not impacting the PM2.5 monitor located at the Libby

Courthouse Annex.

Factor 2: Air quality in potentially included versus excluded areas

County

PM2.5 2001-2003

design value

Lincoln 16.2*

Flathead 9.1

Bonner 8.0

Boundary 8.2

Sanders 6.2

* Lincoln County PM2.5 monitor is located at the Libby Courthouse Annex, Libby, MT.

All adjacent counties to Lincoln, MT are attaining the PM2.5 standard. This factor

played a significant role in the decision making process.
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Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

The following table has the population and population density for Lincoln County and the

adjacent counties.

County 2002 Population 2002 Population Density (pop.

per square mile)

Lincoln 18,665* 5**

Flathead 77,240 15

Bonner 38,205 22

Boundary 10,085 8

Sanders 10,367 4

* Town of Libby, MT population: 2,626;

** Town of Libby, MT population density: 2,020 persons/square mile

The town of Libby, where the PM2.5 problem is located has a much higher population

density than the remainder of Lincoln County or any of the surrounding counties. Also,

due to the commuting patterns, topographical features and meteorology in Lincoln

County (see factors 4, 6 and 7 below), EPA feels the adjacent county populations do not

impact the PM2.5 monitor located at the Libby Courthouse Annex. This factor played a

significant role in the decision making process.

Factor 4: Traffic and commuting patterns

Commuting Information:

Lincoln County, the design value county, has a total of 6,721 commuters.

- Commuters who remain in Lincoln County: 6,177

Flathead County, an adjacent county, has a total of 34,035 commuters.

- Commuters from Flathead County to Lincoln County: 85

- Commuters that remain in Flathead County: 32,956

Bonner County, an adjacent county, has a total of 15,570 commuters.

- Commuters from Bonner County to Lincoln County: 0

- Commuters that remain in Bonner County: 12,968

Boundary County, an adjacent county, has a total of 3,830 commuters.

- Commuters from Boundary County to Lincoln County: 10

- Commuters that remain in Boundary County: 3,310

Sanders County, an adjacent county, has a total of 3,903 commuters.

- Commuters from Sanders County to Lincoln County: 12
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- Commuters that remain in Sanders County: 3,337

The following table has the vehicle miles traveled (thousand miles) for Lincoln County

and the adjacent counties.

County VMT

Lincoln 231

Flathead 756

Bonner 442

Boundary 139

Sanders 93

Based on the analysis for this factor there are no adjacent counties impacting the PM2.5

monitor located at the Libby Courthouse Annex. This factor played a significant role in

the decision making process.

Factor 5: Expected growth

The following table has the population and population growth figures for Lincoln County

and the adjacent counties. (Nonattainment counties are in bold.)

County

2002

Population

Population

Density

Area

(sq. mile)

Growth

(90-00)

% Change

(90-00)

Lincoln 18665 5 3613 1356 8

Flathead 77240 15 5099 15253 26

Bonner 38205 22 1738 10213 38

Boundary 10085 8 1269 1539 18

Sanders 10367 4 2762 1558 18

Based on the analysis for this factor, there is no significant growth, on either an absolute

or a percentage basis, to indicate a contribution to the air quality in Lincoln County. This

factor did not play a significant role in the decision making process.

Factor 6: Meteorology

Libby Montana is located in the northwestern part of the state in a narrow north-south

oriented valley. The ridgetops surrounding Libby are approximately 4,000 feet higher
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than the town. There are no other towns or large emissions sources immediately upwind,

so transport of high background concentrations into Libby is considered unlikely. The

highest PM2.5 concentrations in Libby generally occur during the months of November

through February. During the summer months concentrations typically average less than

half the level of the annual PM2.5 NAAQS, while winter concentrations may double the

NAAQS. The much higher concentrations in winter are related to stagnant weather

conditions dominated by light winds and strong temperature inversions. These

meteorological conditions may trap emissions within the valley for many days. No recent

meteorological data is available for Libby, however, data from Kalispell, MT show calm

wind conditions occur 35 percent of the time in the winter months and only 15 percent of

the time in the spring and summer. Vertical temperature soundings at Great Falls in

Western MT also show a very high frequency of surface temperature inversions in the

winter.

Due to the meteorology conditions in the town and surrounding vicinity of Libby and due

to the topographical features within Lincoln County and more specifically around Libby

(see factor 7 below), that create stagnant weather conditions, EPA feels the adjacent

counties do not impact the PM2.5 monitor located at the Libby Courthouse Annex and

that the nonattainment problem is a localized PM2.5 problem.

Prevailing Wind Directions (%)

County NW SW SE NE

Lincoln 14 37 22 26

Flathead 21 34 22 24

Bonner 14 42 20 24

Boundary 12 40 22 27

Sanders 26 28 24 22

This factor played a significant role in the decision making process.

Factor 7: Geography/topography

Lincoln County, MT

Lincoln County has a land area of 3,675 square miles. The area of concern showing high

PM2.5 concentrations is located within and around the Libby, Montana vicinity. Lincoln

County has numerous geographical or topographical boundaries limiting its airshed to a

very narrow valley including the surrounding vicinity of Libby. The town of Libby has a

total area of 1.3 miles. As of the 2000 census, there are 2,626 people, 1,132 households,

and 669 families residing in the city. The elevation for the town of Libby is 2,601 feet.

The ridgetops surrounding Libby are approximately 4,000 feet higher than the town. The

town sits in a narrow valley that runs in a north-south direction (48°23'17" North,
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115°33'13" West). The Kootenai River runs adjacent to the town in an east-west

direction. The Kootenai Basin is largely mountainous and dominated by three major

ranges. The Rocky Mountain Range and the Flathead Range constitute the eastern

boundary; the Purcell Range roughly bisects it from north to south. The Selkirk and

Cabinet Ranges mark the western boundary. Elevations reach a maximum of about

12,000 feet with most summit elevations between 6,000 and 7,500 feet. Except for a few

areas, the entire watershed is heavily forested (practically all of Lincoln County and a

large portion of the surrounding counties consists of National Forest land). The Kootenai

River has its origins in British Columbia's Kootenay National Park in Canada. From

there it flows 485 miles into northwest Montana and through the towns of Libby and

Troy. From there it flows into northern Idaho, then back into Canada and Kootenay

Lake. Ultimately it joins with the Columbia River. Sixteen miles north of Libby, the

river is held back by Libby Dam, creating a 90-mile long reservoir that reaches into

Canada. The river drops less than 1,000 feet (305 meters) in elevation from Canal Flats

to Kootenay Lake, a distance of over 300 miles (480 km). However, even along the

river’s slow meandering course, valley-bottom widths are generally less than two miles

and are characterized by tree-covered rolling hills with few grassland openings.

Due to the topographical features and meteorological data (see factor 6 above) within and

surrounding the vicinity of Libby resulting in stagnant weather conditions trapping

emissions in the valley, EPA feels the adjacent counties do not impact the PM2.5 monitor

located at the Libby Courthouse Annex. Emissions from adjacent counties would have to

traverse one or more major mountain ranges, in some cases against the prevailing wind

direction, in order to impact the town of Libby.

This factor played a significant role in the decision making process.

Factor 8: Jurisdictional boundaries

No areas in Montana or Idaho were designated nonattainment for the 8-hour ozone

standard on April 15, 2004.

The town of Libby and vicinity within Lincoln County are designated nonattainment for

PM10.

Due to the fact that the town and surrounding vicinity of Libby, Montana was designated

nonattainment for PM10 and did not include the surrounding counties around Lincoln,

MT, EPA believes this factor plays a significant role in the decision making process.

Factor 9: Level of control of emission sources

The following are sources located in Lincoln County, MT but are not considered major

PSD sources.

- Plum Creek Northwest Lumber, Inc. (Ksandka Sawmill), Fortine, MT

- Eureka Pellet Mills, Eureka, MT
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- Genesis Inc. (Troy Mine), Troy, MT

- Lone Pine Timber Industries, Eureka, MT

- Stimson Lumber Mill, Libby, MT (closed - Spring, 2003)

Due to the topographical features and meteorology in Lincoln County (see factors 6 and 7

below) and more specifically surrounding Libby, MT where the PM2.5 problem is

located, EPA believes this factor does not play a significant role in the decision making

process.

6.8.2 Justifications for Changes to EPA Recommendations Contained

in the June 29, 2004 Letters to States

Background: In a letter dated February 25, 2004, the Governor of Montana submitted to

EPA a letter recommending that the PM2.5 nonattainment boundary for Lincoln County,

MT be designated as a partial county. The Governor’s letter did not provide a specific

justification for a partial county recommendation or identify what the partial county

boundaries would be for Lincoln County. On June 29, 2004, EPA responded to

Montana’s recommendation stating that EPA agreed with Montana’s recommended

nonattainment designation for Lincoln County but that EPA intended to modify

Montana’s recommended boundary for the nonattainment area and designate the entire

Lincoln County area as nonattainment for the PM2.5 national ambient air quality

standards.1 In two follow-up letters from Montana dated June 25, 2004 and September 7,

2004, Montana identified specific PM2.5 nonattainment boundaries for Libby, MT along

with a technical justification for the less-than-county request.

EPA’s Recommended Change: Based upon EPA’s review of Montana’s letters dated

June 25, 2004 and September 7, 2004 and subsequent discussions EPA has had with the

Montana Department of Environmental Quality (MT DEQ), EPA is modifying our

original recommendation and identifying the PM2.5 nonattainment boundary area as

follows: 600,000mE, 5,370,000mN east to 620,000mE, 5,370,000mN south to

620,000mE, 5,340,000mN west to 600,000mE, 5,340,000mN north to 600,000mE,

5,370,000mN as identified in Montana’s September 7, 2004 letter. EPA believes these

boundaries are reasonable for the following reasons:

 1

 EPA’s April 1, 2003 “Designations for the Fine Particle National Ambient Air Quality Standards” which

states: “When a rural monitor violates the standard, EPA intends to apply a presumption that the

nonattainment area shall include the full county in which the monitor is located. EPA will consider

recommendations to adjust rural area nonattainment boundaries based on the same factors as it applies to

urban areas, as discussed in question 5 above. Using these factors, a State or Tribe that recommends that a

smaller area should be designated nonattainment should provide convincing evidence that the monitor is

not representative of the full county, that the excluded portions of the county are not source areas

contributing to the nonattainment, and that the excluded portions of the county are meeting the standard.

Similarly, a State or Tribe may recommend that a larger area be designated nonattainment based on

technical information relevant to these factors. Nevertheless, as discussed above, if nonattainment is

demonstrably very localized and is attributable to localized sources, EPA intends to establish nonattainment

area boundaries based on a case-specific evaluation of the nature and extent of the problem.”
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1. As stated under factors 6 and 7 of EPA’s factor analysis for Lincoln County,

meteorology and geographical/topographical features within and surrounding the

town of Libby played a significant role in the decision making process and in

EPA’s consideration to modify the nonattainment boundary to only include the

town of Libby and surrounding vicinity. (See Factors 6 and 7 for more details.)

2. The MT DEQ conducted a winter monitoring study in the Libby, Montana area

from November 2003 through March 2004. This information was submitted to

EPA in MT DEQ’s June 25, 2004 PM2.5 nonattainment boundary area

recommendation for the town of Libby. The monitoring study showed that within

the “T” shape basin where Libby Creek flows into the Kootenai River, significant

drops in PM2.5 occur along the northwestern edge of the Libby valley as well as

the northeastern edge of the valley. Wind speed results showed that there is very

little wind in the Libby area during winter confirming that much higher

concentrations in winter are related to stagnant weather conditions dominated by

light winds and strong temperature inversions. As a result, meteorological

conditions may trap emissions within the valley for many days. In MT DEQ’s

June 25, 2004 recommendation, MT DEQ acknowledged in the boundary analysis

that while monitoring was not conducted further south than 3 miles from the

town’s center, MT DEQ was confident that the boundary that they recommended

in their June 25 letter adequately surrounds the source area for the Libby PM2.5

nonattainment area. EPA disagreed with MT DEQ’s southern boundary

recommendation and in further discussions with MT DEQ, came to an agreement

to extend the southern boundary area to include an additional 20,000 meter UTM

Grids beyond what was recommended in MT DEQ’s June 25, 2004

recommendation. This new boundary agreement is reflected in MT DEQ’s letter

dated September 7, 2004.

Due to the geographical/topographical features and meteorological data within and

surrounding the vicinity of Libby and the study performed by MT DEQ, EPA feels the

surrounding Lincoln County area outside the recommended boundary area does not

impact the PM2.5 monitor located at the Libby Courthouse Annex. Emissions from the

surrounding area within Lincoln County would have to traverse one or more major

mountain ranges, in some cases against the prevailing wind direction, in order to impact

the town of Libby.
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6.9 Region 9 Nonattainment Areas

6.9.1 EPA 9-Factor Analyses for California for the Designation of PM2.5 Nonattainment

Areas

This attachment to the modification letter to California contains EPA’s preliminary evaluation of

the state’s recommended PM2.5nonattainment areas. The recommended areas have been

evaluated to determine if they follow the guidance provided in EPA’s memo of April 1, 2003,

“Designations for the Fine Particle National Ambient Air Quality Standards” from Jeffrey R.

Holmstead, Assistant Administrator of EPA to Region Administrators.

In the April 1, 2003 memo, EPA states that for the purposes of designating PM2.5 nonattainment

areas, it “presumes the entire MSA should be designated as nonattainment.” In areas where there

are multiple MSA’s comprising one larger CMSA, the entire CMSA is the presumptive

nonattainment area. This is based on the assumption that “violations of the PM2.5 NAAQS in

urban areas may be presumed attributable at least in part to contributions from sources

distributed throughout the Metropolitan Area.”

The April 1, 2003 memo also states that in some cases, a State or Tribe may find that a violation

of the PM2.5 standard is attributed to a significant metropolitan-scale component and yet believe

that the Metropolitan Area does not appropriately define the area that should be designated

nonattainment. EPA will consider requests for urban nonattainment area definitions that deviate

from OMB’s metropolitan area definitions on a case-by-case basis, considering the factors

described below:

Emissions in areas potentially included versus excluded from the nonattainment area

Air quality in potentially included versus excluded areas

Population density and degree of urbanization including commercial development in

included versus excluded areas

Traffic and commuting patterns

Expected growth (including extent, pattern and rate of growth)

Meteorology (weather/transport patterns)

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

Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

Level of control of emission sources

This attachment provides EPA’s preliminary conclusions on California’s recommended

PM2.5nonattainment areas with respect to EPA’s April 1, 2003 guidance and the nine factors

that must be considered when designating an area smaller than the Metropolitan Statistical Area.

California has recommended four PM2.5 nonattainment areas:

San Diego County

San Joaquin Valley

South Coast Air Basin

City Of Calexico, Imperial County, California
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6.9.1.1 City of Calexico, Imperial County, California

There are three PM2.5 monitoring sites in Imperial County that are being used to determine this

area’s compliance with the NAAQS: Calexico - Ethel Street, El Centro, and Brawley. When the

State submitted their recommendations for PM2.5 nonattainment areas they used data from the

years 2000 through 2002. This data set indicated that the monitor at Calexico - Ethel Street was

in violation of the annual PM2.5 NAAQS, with a 3-year annual average of 15.6 _g/m3. The

2000-2002 three-year annual averages for El Centro and Brawley were 11.3 _g/m3 and 14.7

_g/m3, respectively.

When the 2003 data set became available, EPA recalculated the three-year annual averages for

these monitoring locations. The most recent three years of data (2001-2003) indicate that while

the three-year annual averages are close to the NAAQS, none of the sites exceed the annual

NAAQS of 15 _g/m3. The 2001-2003 year annual averages for Calexico, El Centro, and

Brawley are 14.3 _g/m3, 11.1 _g/m3, and 14.5 _g/m3 respectively.

It should be noted that the three monitoring sites did not have complete data sets for the 2001-

2003 timeframe. In order to calculate the annual averages, EPA used the data substitution

procedures in "Guideline on Data Handling Conventions for the PM NAAQS” (EPA-454/R-99-

008, 1999).

6.9.1.2 San Diego Area

For the San Diego area, California recommended San Diego County as the PM2.5 nonattainment

area. It includes the entire San Diego MSA.

The presumptive PM2.5 nonattainment area for San Diego is the San Diego MSA which includes

San Diego County in its entirety.

The state’s recommended PM2.5 nonattainment area is the same as EPA’s presumptive

nonattainment area.

Based on EPA’s preliminary nine-factor analysis of California’s recommendation, the

presumptive nonattainment area and all adjacent counties, EPA agrees that California’s

recommendation is an appropriate nonattainment area. We have included comments on each

factor in the pages following.

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment

area

The presumptive boundary for the San Diego MSA is all of San Diego County. The State of

California’s recommended PM2.5 nonattainment area includes all of San Diego County, under

the jurisdiction of the San Diego Air Pollution Control District. All potential emission sources in

the San Diego MSA are included in the State’s state recommended nonattainment area.
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Adjacent counties to San Diego include Orange, Riverside, and Imperial Counties. Emissions

generated in Orange County and Riverside County are included in the state recommended South

Coast nonattainment area. Emissions originating in Imperial County do not contribute to

elevated PM2.5 concentrations in San Diego County because Imperial County is separated from

the San Diego area by the Laguna Mountains and many miles of desert.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 2: Air quality in potentially included versus excluded areas

The State’s recommended boundary includes all violating monitoring sites. Violating monitors

in Orange County and Riverside County are included in the state-recommended South Coast

nonattainment area. There are no monitors in Imperial County that are currently in violation of

the either the 24-hour or annual PM2.5 NAAQS.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

All urbanized areas in the San Diego MSA are included in the state’s recommended boundary

and exist west of the Laguna Mountains, which bisect San Diego County from the north to the

south. Urbanized areas in the adjacent counties of Orange and Riverside fall within the South

Coast nonattainment area. The nearest urbanized area in Imperial County is the El Centro area

which is separated from the San Diego area by the Laguna Mountains and many miles of desert.

The El Centro area is currently not violating either the 24-hour or annual PM2.5 NAAQS.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 4: Traffic and commuting patterns

California’s recommended PM2.5 nonattainment area, San Diego County, contains most of the

VMT for the San Diego MSA. The amount of commuting traffic between San Diego and

Orange or Riverside Counties is minimal and would not contribute significantly to air quality

problems in San Diego County.

Because of the great distance between San Diego is urbanized areas and Imperial County, traffic

and commuting patterns in Imperial County do not contribute to air quality violations in San

Diego County.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.
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Factor 5: Expected growth (including extent, pattern and rate of growth)

Expected growth in the San Diego MSA will be contained in San Diego County. Expected

growth in the adjacent counties of Orange and Riverside will be accounted for in the staterecommended South Coast nonattainment area. Growth in urban areas of Imperial County will

not impact the San Diego MSA due to the great distance between these areas.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 6: Meteorology (weather/transport patterns)

The distribution of high PM2.5 concentrations within the San Diego area appear to be dependent

upon calm-to-light winds and not as dependent upon wind direction. This suggests, as in the

South Coast area, that there is enough activity within the San Diego area to generate high PM2.5

concentrations under many conditions and that high concentrations are not being caused by

adjacent areas such as Orange, Riverside and Imperial Counties.

Because high PM2.5 concentrations occur during periods of calm-to-light wind conditions, the

source of the high PM2.5 concentrations is likely within San Diego County itself. Under these

conditions, it is unlikely that transport is bringing precursors into the County in levels significant

enough to cause violations there.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

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

The San Diego MSA is bounded by the Laguna Mountains to the east, which bisect San Diego

County into a western portion, where the San Diego MSA is located, and an eastern portion

which is rural and adjacent to Imperial County. To the west is the Pacific Ocean. Orange and

Riverside counties are to the north and the U.S.-Mexico border forms the southern boundary.

Emissions originating in Imperial County do not contribute to elevated PM2.5 concentrations in

San Diego County because Imperial County is separated from the San Diego area by the Laguna

Mountains and miles of desert. While there could be some transport of emissions from Orange

or Riverside counties, these areas are included in the state-recommended South Coast

nonattainment area. Any emissions emanating from across the U.S.-Mexico border will need to

be dealt with through the planning process.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.
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Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

The state recommended San Diego County nonattainment area is entirely under the jurisdiction

of the San Diego Air Pollution Control District. To the north of San Diego County is Orange

and Riverside Counties, which are included in the state-recommended South Coast

nonattainment area. Imperial County to the east is under the jurisdiction of the Imperial County

Air Pollution Control District. Imperial County contributes minimally if at all to PM2.5 air

quality in San Diego County because of the distance between the San Diego urban area and

Imperial County and the Laguna Mountain range which effectively separates the San Diego

urban area from Imperial County.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 9: Level of control of emissions sources

Imperial County does not contribute to violations in San Diego County because of the low level

of emissions in the western half of Imperial County, the intervening mountains (extending to

over 4000 ft. in height), and the prevailing westerly winds. There is no significant commute

pattern linking the two areas, since the urbanized portions of San Diego and Imperial County are

separated by more than 100 miles of relatively sparsely populated mountains and desert (the

highway distance from San Diego to El Centro is 117 miles). The two counties are under

separate air quality jurisdictions (San Diego County Air Pollution Control District and Imperial

County Air Pollution Control District) and in separate State air basin planning areas (San Diego

Air Basin and Salton Sea Air Basin). While the coastal portion of San Diego County is highly

urbanized with a population of approximately 3,000,000, the entire Imperial County is rural and

primarily agricultural, with a total County population of approximately 150,000 (population

density of 35 per square mile). San Diego’s average daily VMT is over 75,000,000, compared to

Imperial County’s average daily VMT of approximately 4,215,000.

6.9.1.3 San Joaquin Valley Area

For the San Joaquin Valley, California recommended the San Joaquin Valley (SJV) as the PM2.5

nonattainment area.

This area includes the SJV Air Basin portion of Kern County, and all of Fresno, Kings, Madera,

Merced, San Joaquin, Stanislaus and Tulare counties.

The presumptive nonattainment area includes the MSA’s that have violations of the PM2.5

NAAQS. These include the following MSA’s: Bakersfield (Kern County), Fresno (Fresno

County), Merced (Merced County), Modesto (Stanislaus County), and Visalia-Tulare-Porterville

(Tulare County).

The only portion of the presumptive nonattainment area excluded from the state’s SJV

recommendation is Eastern Kern County (EKC), which is in a separate air basin (Mojave Desert)
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and is separated from the SJV by the Sierra Nevada and Tehachapi Mountains and significant

distance.

The seventeen counties adjacent to the presumptive area and excluded from the state’s

recommendation (Alameda, Amador, Calaveras, Contra Costa, Inyo, Los Angeles, Mariposa,

Mono, Monterey, Sacramento, San Benito, San Bernardino, San Luis Obispo, Santa Barbara,

Santa Clara, Tuolumne, Ventura) are not in the SJV. These areas are either mountainous,

separated from SJV by mountains, separated from SJV by significant distance or a combination

of all of three. Thus, this indicates that these counties should not be included in the San Joaquin

Valley nonattainment area.

Based on the following nine-factor analysis, EPA concurs with the State’s recommendation to

include San Joaquin and Kings counties and to exclude that portion of Kern County east of the

Tehachapi and Sierra Nevada Mountains. The excluded portion of Kern County is a rural, desert

area in a separate State air basin (Mojave Desert) from the San Joaquin Valley (SJV). We have

included comments on each factor in the pages following.

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment

area
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The EKC emissions are a tiny fraction of SJV emissions, as shown in the table below.

Comparison of PM2.5 and PM2.5 Precursor Emissions

Eastern Kern County vs. San Joaquin Valley

Source: California Air Resources Board,

2004 California Almanac of Emissions & Air Quality,

2003 Estimated Annual Average Emissions in Tons per Day

VOC NOx SO2 PM2.5

Eastern Kern County 13.2 37.9 3.9 9.5

San Joaquin Valley 396.7 504.9 26.6 150.5

California’s recommended PM2.5nonattainment area only excludes the EKC which contributes

only a tiny fraction of the emissions in the presumptive nonattainment area. This excluded area

is separated from the SJV by the Tehachapi and Sierra Nevada mountains. Thus, the excluded

area does not cause violations of the NAAQS in the SJV.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the San Joaquin Valley nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 2: Air Quality in potentially included versus excluded areas

California’s recommended PM2.5 nonattainment area, the SJV, contains all violating monitors.

Thus, violations are not occurring in the excluded portions of the metropolitan statistical area.

With respect to adjacent counties, the only monitors that violate the NAAQS in an adjacent

county are in counties that have been recommended as part of the Los Angeles nonattainment

area and are separated from the SJV by mountains.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

The population of the EKC is approximately 120,000, compared to the SJV population of

approximately 3,500,000. EKC has a very low population density (47 per square mile), degree

of urbanization, and projected population growth, since the major source of EKC employment is

the military.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the San Joaquin Valley by topography and/or distance. Based on their location
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and this factor, these counties should not be included in the San Joaquin Valley nonattainment

area.

EPA concludes that analysis of this factor supports designating the San Joaquin Valley as the

nonattainment area for PM2.5.

Factor 4: Traffic and commuting patterns

Average daily VMT for EKC is approximately 4,200,000 compared to SJV VMT of

approximately 85,000,000. There is an insignificant volume of daily commute traffic between

EKC and SJV.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 5: Expected growth (including extent, pattern and rate of growth)

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 6: Meteorology (weather/transport patterns)

There are typically westerly winds in the southern SJV, which have the potential to carry some

levels of PM2.5 precursors from SJV to EKC, although the mountains (elevations from 4,064 ft.

at the Tehachapi Pass in the south to 9,875 ft. at Sunday Peak in the north) serve as a barrier to

transport. Attainment of the PM2.5 and 8-hour ozone NAAQS within SJV will require adoption

of Statewide and SJV controls at a level of stringency sufficient to ensure that transport from

SJV to EKC will be further minimized. Transport from EKC to SJV is insignificant, because of

the high mountains, the prevailing wind direction, and the insignificant level of emissions in

EKC.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.
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Factor 7: Geography/topography (mountain ranges or other air basin boundaries)

California’s recommended PM2.5 nonattainment area, the SJV, is bounded on the west by the

Coast Ranges, on the south by the Tehachapi mountains, and on the east by the Sierra Nevada

mountains. These mountains act as a barrier to pollution. Violations of the PM2.5 NAAQS are

not caused by areas outside the SJV.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

The EKC is excluded from the SJV nonattainment area because it is under the jurisdiction of the

Kern County Air Pollution Control District, and in a separate air basin, The Mojave Desert Air

Basin. SJV nonattainment areas are in the same separate air basin and are all under the

jurisdiction of the SJV Unified Air Pollution Control District. The California Air Resources

Board coordinates Statewide planning, oversees implementation of intra-state planning

requirements (including transport mitigation), and coordinates inter-basin planning, to the extent

necessary.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 9: Level of control of emissions sources

Both EKC and SJV are designated nonattainment for the 8-hour ozone NAAQS (with the

exception of the extreme northeastern corner of EKC, which is designated attainment). Control

measures developed to attain the 8-hour ozone NAAQS in both the EKC and SJV will likely

focus on coordinated State initiatives to reduce precursor emissions from mobile sources. The

State also is aggressively pursuing Statewide controls on primary PM emitted by mobile sources

as part of a diesel risk reduction initiative.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.
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6.9.1.4 South Coast Air Basin Area

For the Los Angeles nonattainment area, California recommended the South Coast Air Basin as

the PM2.5 nonattainment area. This area includes the South Coast Air Basin portions of Los

Angeles, Orange, Riverside and San Bernardino counties.

The presumptive nonattainment area is the Los Angeles CMSA, which includes the counties of

Los Angeles, Orange, Riverside, San Bernardino and Ventura.

Based on EPA’s preliminary nine-factor analysis of California’s recommendation, the

presumptive nonattainment area and all adjacent counties, EPA agrees that California’s

recommendation is an appropriate nonattainment area for the Los Angeles area (note: The “Los

Angeles” area consists of the urban areas of the city of Los Angeles and surrounding developed

areas within the Los Angeles basin). We have included comments on each factor in the pages

following.
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6-367
6-368

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment area

PM SO2 NOX VOC Amm Carbon Crustal SO2 - Ex Pt NOx - Ex Pt

LScore

Cumulative 

L-Score

C/MSA Total 69,872 22,119 530,780465,495 61,094 41,151 23,840 10,900476,347

C A Los Angeles 28,855 16,629 276,002251,469 14,252 19,365 7,097 7,460254,66853.4 53.4

C A San Bernardino 17,741 3,246 109,488 50,278 21,541 8,147 8,022 1,602 81,59719.7 73.1

C A Orange 8,585 1,129 73,846 89,987 7,330 5,714 2,466 974 71,37412.7 85.8

C A Riverside 10,476 674 52,809 46,232 16,164 5,280 4,921 575 51,31510.0 95.8

C A Ventura 4,215 441 18,635 27,529 1,807 2,645 1,334 289 17,393 4.2 100.0

NV Clark 13,408 48,089 76,295 50,366 2,362 3,897 8,880 4,583 45,59440.5

CA Kern 13,712 5,468 71,174 41,469 11,496 7,469 5,296 1,651 54,60416.5

CA San Diego 12,683 2,007 76,341 95,358 6,015 7,297 4,827 1,748 73,04614.8

CA Santa Barbara 4,201 1,301 14,919 24,755 2,032 2,764 1,292 280 13,355 4.5

CA Imperial 4,931 264 16,683 11,254 8,473 2,151 2,523 195 15,887 3.6

AZ Mohave 3,037 695 12,691 12,837 1,231 2,021 959 688 11,935 3.3

CA Inyo 2,764 394 1,694 3,247 747 2,133 564 173 1,424 2.0

AZ La Paz 810 142 3,100 2,407 503 319 483 142 3,062 0.7

Area Total 125,418 80,479 803,677 707,188 93,953 69,202 48,664 20,360 695,254

ST COU Total Emissions, 2001 (tons)

Weighted 

Emisssions
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2003 Estimated Non-Natural Emissions (tons per day)

County South Coast Air Basin

portion of Los Angeles CMSA

(area included in nonattainment area)

non-South Coast Air Basin

portion of Los Angeles CMSA

(area excluded from nonattainment

area)

 Emissions

(included area)

Emissions

(excluded area)

ROG* NOX SOX PM2.5 ROG* NOX SOX PM2.5

Los Angeles 480.80 630.10 52.00 55.90 20.90 26.90 0.60 8.90

(As a

percentage)

48.8% 48.0% 71.5% 34.7% 2.1% 2.0% 0.8% 5.5%

Orange 159.40 174.10 6.90 17.80

(As a

percentage)

16.2% 13.3% 9.5% 11.0%

Riverside 79.00 125.00 1.90 16.00 17.20 29.90 0.40 7.40

(As a

percentage)

8.0% 9.5% 2.6% 9.9% 1.7% 2.3% 0.6% 4.6%

San

Bernardino

85.00 115.50 2.20 16.00 87.30 160.90 7.40 28.40

(As a

percentage)

8.6% 8.8% 3.0% 9.9% 8.9% 12.3% 10.2% 17.6%

Ventura (land

area)

54.71 50.75 1.31 10.80

(As a

percentage)

5.6% 3.9% 1.8% 6.7%

Total 804.20 1044.70 63.00 105.70 180.11 268.45 9.71 55.50

(As a

percentage)

81.7% 79.6% 86.6% 65.6% 18.3% 20.4% 13.4% 34.4%

*(excluding non-anthropogenic, aka “natural” emissions)

ROG is defined as “Reactive Organic Gas”

Factor 1 (continued): Emissions in areas potentially included versus excluded from the

nonattainment area

In the review of this factor, data from EPA’s Emission Inventory and California Air Resources

Board (CARB) has been used. This data is displayed in Figures 1.1 and 1.2. The CARB data

was useful because it allowed calculation of included and excluded areas’ emission inventories.

Also, EPA produced a weighted emission index, referred to as an “L-score” for each county,

which is another method of examining emission levels in various counties.

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, contains most

of the anthropogenic emissions in the Los Angeles CMSA. The only excluded areas with

significant emissions are population centers (Palm Springs, Lancaster-Palmdale and VictorvilleApple Valley-Hesperia) significantly north or east of Los Angeles. These areas are separated

from the Los Angeles area by the San Gabriel, San Bernardino and San Jacinto mountain ranges,
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which contain the Los Angeles PM2.5 problem to the Los Angeles area. It is not a problem in

the excluded areas and prevailing winds in the excluded areas are generally away from the Los

Angeles area. Thus, emissions in the excluded areas are not causing or contributing to violations

in the Los Angeles area.

The other excluded area is Ventura County, which produces a small portion of the emissions in

the Los Angeles CMSA. Most of the development and population in Ventura County is located

away from the Los Angeles area and much of the county is separated from the Los Angeles area

by mountains.

Six counties adjacent to the Los Angeles CMSA (Clark, NV; Imperial, CA; Inyo, CA; La Paz,

AZ; Mohave, AZ; and Santa Barbara, CA) are separated from the Los Angeles area by great

distance, mountain ranges, desert or a combination of all three. Thus, this indicates that these

counties should not be included in the Los Angeles nonattainment area.

Two counties adjacent to the Los Angeles CMSA are in separate nonattainment areas (e.g., Kern,

San Diego) and are separated from the Los Angeles area by mountain ranges. Thus, they are not

included in the Los Angeles nonattainment area for those reasons.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

Factor 2: Air Quality in potentially included versus excluded areas

C/MSA Total 27.4 N A 28.9 N A 29.8 N A

C A Los Angeles 22.8 N A 24.4 N A 25.9 N A

C A San Bernardino 24.5 N A 25.9 N A 25.8 N A

C A Orange 18.6 N A 20.3 N A 22.4 N A

C A Riverside 27.4 N A 28.9 N A 29.8 N A

C A Ventura 14.5 A 14.8 A 14.5 A

NV Clark 11.0 A 10.9 A 11.0 A

CA Kern 21.8 NA 22.8 NA 23.7 NA

CA San Diego 15.9 NA 16.4 NA 17.1 NA

CA Santa Barbara 9.5 A 9.9 A 13.0 a

CA Imperial 9.1 A 15.6 NA 15.7 NA

AZ Mohave 

CA Inyo 6.2 A 7.8 a 7.6 a

AZ La Paz 

Area Total 27.4 NA 28.9 NA 29.8 NA

'01-'03 '00-'02 '99-'01

ST COU

Design Values

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, contains all

violating monitors of the Los Angeles CMSA. Thus, violations are not occurring in the excluded
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portions of the metropolitan area. With respect to adjacent counties, the only monitor that

violates in an adjacent county is in Kern County which will be part of the SJV nonattainment

area. This area is separated from the Los Angeles area by two mountain ranges.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

Population and Population Density

County South Coast Air Basin

portion of Los Angeles CMSA

(area included in nonattainment area)

non-South Coast Air Basin

portion of Los Angeles CMSA

(area excluded from nonattainment area)

 Population

(included area)

Population

Density

(included area)

Population

(excluded area)

Population Density

(excluded area)

Los Angeles *9,222,000 *3,693 *298,000 *190

Orange 2,846,289 3,607 --- ---

Riverside *1,199,000 *544 *347,000 *68

San Bernardino *1,330,000 *1,057 *379,000 *20

Ventura --- --- 753,197 425

Total *14,596,289 *2,164 *1,777,000 *65

Source: U.S. Census, 2000

*figure based on estimate of partial county population and/or population density

California’s recommended nonattainment area has a population density of 2164 persons per

square mile. The excluded portion of the Los Angeles C/MSA has a population density of 65

persons per square mile. The recommended nonattainment area contains the densely populated

portions of the Los Angeles C/MSA. It also contains 89% of the C/MSA’s population.

Furthermore, the excluded areas consist of areas separated from the included areas by

topography and/or sparsely populated deserts.

Counties adjacent to the C/MSA are separated from the Los Angeles area by deserts and great

distance and are not included in the nonattainment area for that reason.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.
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Factor 4: Traffic and commuting patterns

Vehicle Miles Traveled

County South Coast Air Basin

portion of Los Angeles CMSA

(area included in nonattainment area)

Non-South Coast Air Basin

portion of Los Angeles CMSA

(area excluded from nonattainment

area)

Average Daily

Vehicle Miles

Traveled

(included area)

VMT as a

percentage of

 LA CMSA

(included area)

Average Daily

Vehicle Miles

Traveled

(excluded area)

VMT as a

percentage of

 LA CMSA

(excluded area)

Los Angeles 179,875,902 47.5 3,935,115 1.0

Orange 67,855,304 17.9 --- ---

Riverside 37,266,851 9.8 18,478,676 4.9

San Bernardino 35,448,320 9.4 17,872,337 4.7

Ventura --- --- 18,215,281 4.8

Total 320,446,377 84.6 58,501,409 15.4

Appendix C: Surface Area, Population, and Average Daily Vehicle Miles Traveled.

California’s recommended PM2.5nonattainment area, the South Coast Air Basin, contains most

(84.6%) of the Vehicle Miles Traveled (VMT) for the Los Angeles C/MSA.

Other portions of the Los Angeles C/MSA outside the South Coast Air Basin account for 15.4%

of the VMT for the Los Angeles CMSA. The areas outside the South Coast Air Basin in Los

Angeles, Riverside and San Bernardino counties account for 10.6% of the VMT in the Los

Angeles CMSA, however, these areas are, for the most part, only sparsely populated desert areas

separated from the Los Angeles area by the San Gabriel, San Bernardino, and San Jacinto

Mountains. The area outside the South Coast Air Basin in Ventura County accounts for 4.8% of

the VMT in the Los Angeles CMSA. Most of the population in Ventura County is in the

Ventura-Oxnard area. We believe that the distribution of VMT in Ventura County is similar to

population, and thus that most of the VMT in Ventura County is in the Ventura-Oxnard area.

This area is approximately 35 miles from the nearest violating monitor in the Los Angeles area

and is separated from the Los Angeles area by the Santa Monica Mountains and Simi Hills and

thus does not contribute to violations in the Los Angeles area. The Ventura County community

closest to Los Angeles county is Simi Valley; however, its population is only 15% of the entire

county and is separated from the Los Angeles area by the Santa Susana mountains, Simi Hills

and other topography in the area. We believe that a similarly small proportion of Ventura

County VMT is in Simi Valley. Based on VMT data for Ventura County, we believe that this

factor does not show that Ventura areas are causing violations in the Los Angeles area.

There are several counties adjacent to the Los Angeles CMSA (Clark, NV; Imperial, CA; Inyo,

CA; Kern, CA; La Paz, AZ; Mohave, AZ; Santa Barbara, CA; San Diego, CA). None of these

counties will be included in the Los Angeles nonattainment area based on this factor because
6-373

these areas are too distant from the Los Angeles area, there is little, if any, commuting to the Los

Angeles area from these counties, and they are separated by geography from the Los Angeles

area. With respect to this factor, these areas do not cause or contribute to violations in the Los

Angeles area.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.
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Factor 5: Expected growth (including extent, pattern and rate of growth)

2002 Area (sq 

miles)

Density 

'02

Growth '90-

'00

Pct 

chng '90-

'00

1990 2000 Growth 

'02-'10

Pct chng 

'02-'10

C/MSA Total 17,044,188 33,966 502 1,842,116 1 3 14,531,52916,373,6451891964 1 1

C A Los Angeles 9,806,577 4,060 2,415 656,174 7 8,863,1649,519,338 797875 8

C A San Bernardino 1,816,072 20,062 9 1 291,054 2 1 1,418,3801,709,434 371735 2 0

C A Orange 2,938,507 790 3,720 435,733 1 8 2,410,5562,846,289 225269 8

C A Riverside 1,699,112 7,208 236 374,974 3 2 1,170,4131,545,387 426425 2 5

C A Ventura 783,920 1,846 425 84,181 1 3 669,016 753,197 70660 9

NV Clark 1,522,164 7,911 192 634,306 86 741,459 1,375,765 447184 29

CA Kern 694,059 8,142 85 118,168 22 543,477 661,645 165759 24

CA San Diego 2,906,660 4,205 691 315,817 13 2,498,016 2,813,833 534776 18

CA Santa Barbara 403,084 2,739 147 29,739 8 369,608 399,347 65373 16

CA Imperial 146,248 4,175 35 33,058 30 109,303 142,361 75337 52

AZ Mohave 165,593 13,312 12 61,535 66 93,497 155,032 28810 17

CA Inyo 18,214 10,192 2 -336 -2 18,281 17,945 1233 7

AZ La Paz 19,517 4,500 4 5,871 42 13,844 19,715 5579 29

Area Total 22,919,727 89,142 257 3,040,274 16 18,919,01421,959,2883216015 14

Population & Area Additional Population Info

ST COU
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California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, contains most

of the expected growth for the Los Angeles C/MSA. The areas in the Los Angeles C/MSA

experiencing the greatest population growth during the 1990's were Riverside and San

Bernardino counties with growth rates of 21% and 32% respectively. This high rate of growth is

expected to continue in these counties. The recommended nonattainment area contains the

portions of these counties on the edge and beyond the Los Angeles suburbs, so likely growth and

expansion of the populated areas will occur within the recommended nonattainment area.

Ventura County is outside the recommended area, but inside the Los Angeles C/MSA. Ventura’s

growth rate is projected to be 9% through 2010 compared to the slowest growth areas, Los

Angeles and Orange counties where growth rates of 8% are projected. Furthermore, Simi

Valley, the area of Ventura in closest proximity to Los Angeles, has experienced a slowing of

growth and appears to be largely built out. Thus, we do not expect high rates of growth in this

area either.

Some counties adjacent to the C/MSA have high rates of growth and/or are projected to;

however, these counties are separated from the Los Angeles area and its suburbs by some or all

of the following: great distances, mountain ranges, deserts and sparsely populated areas and thus

do not contribute or cause violations in the Los Angeles area.

Based on analysis of this factor, the recommended area includes the Los Angeles area and nearby

areas of expected growth, so the recommended area is appropriate. EPA concludes that analysis

of this factor supports designating the South Coast Air Basin as the nonattainment area for the

Los Angeles Metropolitan Area.

Factor 6: Meteorology (weather/transport patterns)

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, experiences

high PM2.5 concentrations throughout the area and these concentrations may occur any time of

year. Generally, the highest concentrations occur when winds are light and the atmosphere is

stable.

Based on an analysis of wind strength and direction associated with PM2.5 concentrations, high

concentrations are found throughout the South Coast Air Basin, and they tend to occur when

winds are light, especially when the average wind speed is below 4 mph. At most monitors, high

PM2.5 concentrations can occur regardless of the wind direction; in fact, most monitors have a

bi-modal distribution of high PM2.5 concentrations with respect to wind direction. Most of these

monitors have the same bi-modal distribution of average winds as well, generally from the west

to northwest and also from the southeast. It appears that calm to light winds are a more

important factor than the direction from which those winds originate.

The abundance of sources in the South Coast Air Basin and widespread distribution of high

PM2.5 concentrations, dependent upon calm-to-light winds and not as dependent upon wind

direction suggests that there is enough activity within the basin to generate high PM2.5

concentrations under many conditions and that high concentrations are not being caused by

adjacent areas.
6-376

Because mountains nearly surround the South Coast Air Basin, and high PM2.5 concentrations

occur during periods of calm-to-light wind conditions, the source of the high PM2.5

concentrations is likely within South Coast Air Basin itself. Under these conditions, it is

unlikely that transport is bringing precursors into the basin in levels significant enough to cause

violations there.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

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

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, is bounded on

the southwest by the Pacific Ocean, on the west by the Santa Monica, Santa Susana Mountains

and Simi Hills, on the north by the San Gabriel Mountains, on the northeast by the San

Bernardino, on the east by the San Jacinto Mountains and on the south by the Santa Ana and

coast range mountains. These hills and mountain ranges have elevations of 2,000 to well over

10,000 feet and act as barriers to pollution. Thus, violations in the Los Angeles area are not

caused or contributed to by areas outside the South Coast Air Basin.

The excluded areas of the Los Angeles CMSA are separated from the Los Angeles area by the

aforementioned mountains and also great distances, and/or deserts.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

The five counties of the Los Angeles CMSA comprise 33,954 square miles. This area is

equivalent to a square that is 184 miles long and 184 miles wide. The Los Angeles metropolitan

and urbanized areas, although large, are only a small fraction of the entire Los Angeles CMSA,

however, since Los Angeles’ development occupies small portions of the area’s very large

counties, especially Riverside, San Bernardino and Ventura counties, and because CMSA’s are

comprised of units no smaller than counties (except in New England), this CMSA is much larger

than the Los Angeles area. Although this is the presumptive nonattainment area, it is much

larger than the Los Angeles area. Furthermore, it is much larger than the area with PM2.5

NAAQS violations and its accompanying source areas.

The CMSA encompasses fully five different counties, four different local air districts, coastal

regions, alpine mountain regions as well as both low and high deserts.

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, is under the

jurisdiction of the South Coast Air Quality Management District and includes Los Angeles and

its adjacent urban areas, including those in other counties.
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The other air districts within the Los Angeles C/MSA are separate agencies that due to

geography and distance from Los Angeles, are not included in the Los Angeles nonattainment

area.

To the west of the South Coast Air Basin is the Ventura County Air Pollution Control District,

which has been a separate air quality planning entity, with its own board of elected officials and

distinct responsibilities for all air quality planning, regulatory development, enforcement, and

public participation activities, with the exception of those programs that are conducted under the

jurisdiction of a State agency (mobile source standards, consumer products, pesticides, motor

vehicle inspection and maintenance, etc.). Because of the long history of effective statewide

planning and independent agency planning and because of differences in structure and approach

between the air pollution control boards of the Ventura and South Coast, it is likely that

compelling the two areas to share jurisdictional responsibility for air quality planning in an

expanded nonattainment area would interfere with, rather than promote, harmonious and

efficient air quality planning. Ventura County, although given an attainment designation for

PM2.5, would nonetheless continue its efforts to reduce direct and indirect emissions, as

explained further in the analysis of Factor 9.

To the northeast of South Coast Air Basin are the Antelope Valley Air Pollution Control District

and the Mojave Desert Air Quality Management District. These areas, although part of the Los

Angeles CMSA, are separated from the Los Angeles area by the San Gabriel and San Bernardino

mountain ranges, which have elevations over 10,000 feet. For that reason, these areas should not

be included in the Los Angeles nonattainment area.

Moreover, the South Coast AQMD has a long history of analyzing and addressing existing and

potential transport problems affecting downwind jurisdictions. Finally, coordinated rule

development and transport mitigation occurs throughout California because of various provisions

of the California Clean Air Act and subsequent legislation, along with the activities of the

California Air Pollution Control Officers Association.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

Factor 9: Level of control of emissions sources

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, has an extreme

designation for the 1-hour ozone standard. It has also been designated ‘severe-17’ for the 8-hour

ozone standard. The area has some of the most stringent controls in the nation.

This factor is not relevant for other Los Angeles C/MSA areas in the Mojave Desert because they

are separated from the Los Angeles area by mountains.

Ventura County is also in large part, separate from the Los Angeles area by topography and

distance, with just one community near Los Angeles County (although this area, Simi Valley, is

also separated from Los Angeles by a mountain pass). Nevertheless, the level of control of

emissions sources in Ventura County is already high and expected to become more stringent,
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even without a nonattainment designation in Ventura County. The nature of this control is

summarized below:

(1) Ventura County APCD and South Coast AQMD already have a very high level of control of

PM precursor emissions, and the agencies are undertaking further progressive control strategy

development activities to achieve further control as needed to attain and maintain the NAAQS.

(2) Although it is not proposed to be designated nonattainment for the federal PM2.5 NAAQS,

Ventura is designated nonattainment for the extremely stringent California PM10 NAAQS and

must therefore pursue feasible controls to reduce PM concentrations.

(3) The County is also classified as a moderate nonattainment area for the Federal 8-hour ozone

NAAQS. Since the two principal ozone precursors are also PM precursors in Ventura, the

Ventura County APCD must continue to pursue stringent controls of NOx and VOC in order to

attain the 8-hour ozone NAAQS and these controls will benefit PM concentrations.

(4) A large part of the PM precursors are under the State's jurisdiction, and the involved State

agencies are planning to adopt additional stringent emission controls on a Statewide basis.

(5) Attaining the PM2.5 NAAQS is expected to require the South Coast AQMD and the State to

adopt a level of emissions control far in excess of what would be needed to ensure continued

maintenance in Ventura County.

Thus, designating Ventura County as part of the South Coast PM2.5 nonattainment area is not

likely to affect the level of emissions control applicable in the area or upwind in the South Coast.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.
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6.9.2 Justifications for Changes to EPA Recommendations Contained in the June 29,

2004 Letters to States

TECHNICAL SUPPORT DOCUMENT

U.S. EPA Region 9

Unclassifiable/Attainment Designation

for

Certain Areas in Southeastern San Diego County

for

The PM2.5 NAAQS

Includes the Tribal Areas of The:

Campo Band of Kumeyaay Indians

Cuyapaipe Band of Kumeyaay Indians

La Posta Band of Mission Indians

and

Manzanita Tribal Lands
6-380

Southeastern San Diego County Unclassifiable/Attainment Areas for the PM2.5 NAAQS:

Southeastern San Diego County Indian Reservations

[Note: The non-tribal areas in the vicinity of the designated unclassifiable/attainment areas are

under California’s jurisdiction and are part of a county-based area that we are designating as

nonattainment. The State of California recommended designating all of San Diego County as a

single PM2.5 nonattainment area. This recommendation is consistent with presumptions that

follow our guidance on designating PM2.5 nonattainment areas. EPA agrees with the State of

California’s recommendation.]

This section applies to the portion of San Diego County listed below1:

La Posta Areas #1 and #2

Cuyapaipe Area

Manzanita Area

Campo Areas #1 and #2

The four tribes that occupy these six areas did not submit recommendations to EPA.

These areas, which approximate the boundaries of the reservations of the four Tribes in

southeastern San Diego County, are designated unclassifiable/attainment. Based on their

location and other factors, we have determined that these areas do not violate the PM2.5 National

Ambient Air Quality Standards (NAAQS). We also believe that these areas do not contribute to

PM2.5 in other areas.

Although the areas are surrounded by a countywide nonattainment area, the United States has a

unique legal relationship with tribal governments which derives from the United States

Constitution, treaties, statutes, Executive Orders and court decisions, and is commonly referred

to as the Federal government’s trust relationship with Tribes. Guidelines for EPA’s role in this

relationship are outlined in the EPA Policy for the Administration of Environmental Programs on

Indian Reservations (“1984 Indian Policy”) which was issued in 1984 and has been reaffirmed

by successor administrations.

The 1984 Indian Policy states that in the course of protecting human health and the environment,

EPA should recognize tribal governments as sovereign entities with primary authority and

responsibility for their members, and in keeping with this principle of tribal self-government,

view tribal governments as the appropriate non-federal parties for making decisions and carrying

out program responsibilities affecting their reservations and their members. Where tribes have

not assumed delegable programs, EPA retains responsibility for managing federal programs on

reservations. Correspondingly, as a matter of federal case law, absent an express delegation of

authority by Congress to a State, States lack civil regulatory jurisdiction over tribes. Respect for,

and protection of, this division of jurisdiction is an integral part of the federal trust responsibility.

 1

 See “Southeastern San Diego County Unclassifiable/Attainment Areas For The PM2.5 NAAQS" and

“Southeastern San Diego County Unclassifiable/Attainment Area Descriptions” in this document for further

description of these areas.
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Based on EPA’s own evaluation of the nine factors for these four tribes in southeastern San

Diego County, EPA believes that a designation of unclassifiable/attainment is appropriate and is

consistent with the definition of nonattainment in §107(d)(1) of the Clean Air Act.

The justification for this designation is that these tribal areas are small in area, population and

commercial development, and are located approximately 40 miles from San Diego and are

separated from San Diego by mountain ranges, deserts and uninhabited land. Based on the

nine-factor analysis presented below, EPA has concluded that activities within these tribal lands

do not cause or contribute to PM2.5 in San Diego County, and thus are appropriately excluded

from the surrounding San Diego County PM2.5 nonattainment area and designated as individual

unclassifiable/attainment areas for the PM2.5 NAAQS. We also note that our decision to

exclude these areas from the surrounding County-wide PM2.5 nonattainment area is consistent

with the designations we recently made for these same areas for the 8-hour ozone NAAQS.

Nine-Factor Analysis:

Southeastern San Diego

Unclassifiable/Attainment Areas for the PM2.5 NAAQS

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment

area

The Campo, Cuyapaipe, La Posta, Manzanita tribal areas are designated as

unclassifiable/attainment areas because their small size and eastern geographical position make

them unlikely causes or recipients of San Diego area PM2.5 exceedances.

The tribal areas are small and have very low emissions; they are also in the southeastern corner

of the county, generally downwind of areas with high observed annual PM2.5 levels. Therefore,

they are not contributors to San Diego area PM2.5 exceedances.

Nor are the proposed tribal unclassifiable/attainment areas likely recipients of PM2.5 from the

San Diego area. They are higher than the locations that experience high PM2.5, and east of

blocking mountain ranges.

Overall, PM2.5 formation is less well understood than ozone. In addition, since we are

concerned here with the annual standard, one could not just examine a few extreme episodes, but

instead must look at multiple conditions throughout the year. A fuller understanding may not be

available until an attainment plan and modeling are developed. So, for purposes of determining

the appropriate designation status for these tribal areas, this discussion will focus on the different

potentials for pollutant transport to the areas during summer and winter.

When monthly average PM2.5 exceeds 15 _g/m3, that month contributes to an annual average

over 15, and hence to exceedances of the standard. While this can occur in May or June,

concentrations exceed 15 more frequently and by a greater amount during the winter or wet

season, roughly October through March. This is consistent with the expected enhancement of
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PM2.5 levels during conditions of high humidity due to the sulfate formation in the aqueous

phase.

As was described in EPA's designation for 8-hour ozone2 page 34 (2004), summer temperature

inversions, which restrict vertical dispersion and hence lead to high pollution levels, typically

occur below or about equal to the elevation of Alpine, 2000 feet. This finding is based on

meteorological modeling and analyses performed by the San Diego County Air Pollution Control

District (APCD), as well as on ozone measurements that showed ozone confined to a layer at

about this elevation. Unfortunately there is no PM2.5 data available from Alpine, but using

similar reasoning as for ozone, this elevation limitation prevents significant transport of

pollutants to the four tribal areas, which are 12 miles further inland, and range from 600 to 1300

feet higher. If a polluted layer were very thick, it could conceivably reach the lowest area,

Campo #2, by way of the canyon containing Cottonwood Hauser Creek. However, the Campo

areas are sheltered from the west by a westward spur of the Laguna Mountains, with

accompanying complex terrain. Thus for the summer months, the tribal areas are unlikely to

receive elevated PM2.5 levels.

For the winter months, when PM2.5 levels are higher, inversions occur more often at the surface

than aloft, and tend to be less intense than in summer. The inversions aloft also tend to have a

base at greater height above the ground, and so to be less constraining of pollutant dispersion.3

Surface-based inversions could hold pollutants near the ground. But in order for pollution

generated in the more urban portions of San Diego County to reach the tribal areas, they must be

transported far inland and uphill.

While winter winds are predominantly from the northwest, as in summer, they are slower. Under

some conditions, flow can even be from the northeast, down the canyons instead of up, due to the

Great Basin high pressure system that persists during winter (a strong version of this is the

"Santa Ana" winds). Thus there is less tendency for pollution to be transported inland. Upslope

flow that occurs due to surface heating could lead to pollutant transport uphill, but it is unlikely

to extend to the tribal areas. The Great Basin high just mentioned would tend to weaken the

upslope flow. In addition, in comparison to summer there is simply less heating to drive the

flow. Finally, the position of the tribal areas essentially at the mountain range crest means that

there is comparatively little slope to convert the expansion from heating into horizontal

movement of polluted air upslope. Upslope flow from the east side of the range would also tend

to retard upslope flow from the west. Therefore, during winter it is unlikely that elevated PM2.5

levels would reach these tribal areas.

One final piece of evidence to consider is the attaining air quality of Imperial County to the east.

The nearest monitor east of the tribal areas is at El Centro, where the annual design value is 9.1

_g/m3,

4

 well below the standard. While not completely conclusive due to the distance involved,

 2

 U.S. EPA., “8-hour Ozone Designation, Technical Support Document”, Chapter 3,

3

 California Air Resources Board, “Climate of the San Diego Air Basin,” December 1974.

4

 U.S. EPA, Air Quality Subsystem (AQS), 2001-2003.
6-383

this reading is consistent with the idea that the mountain range central to San Diego County is a

barrier to the movement PM2.5 from the urbanized western portion of the county, and that the

tribal areas should not be part of the nonattainment area.

Factor 2: Air Quality in potentially included versus excluded areas:

To the west, the monitor nearest these tribal areas is El Cajon located approximately 30 miles

west, which has a design value slightly above the PM2.5 NAAQS at 15.7 _g/m3.

5

 To the east,

the monitor nearest these tribal areas is El Centro located approximately 45 miles east, which has

a design value well below the PM2.5 NAAQS, at 9.1 _g/m3.

6

EPA believes the air quality in these tribal areas attains the PM2.5 NAAQS because there are

few sources in the area and it is separated from the violating monitors by both distance and

topography.

The violating monitor at El Cajon is at approximately 435 feet elevation and is separated from

these tribal areas by the Laguna Mountains. Between El Cajon and these tribal areas, the Laguna

Mountains have elevations generally in the 3000-6000 foot range. The mountains nearest to the

tribal areas are generally in the 4000-6000 foot range.

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

The tribal areas are not urbanized and are sparsely populated. Nearly all of the tribal lands

discussed here have a population density of less than 50 persons per square mile. The maximum

population density on these tribal lands is less than 500 persons per square mile, and even these

areas account for only a negligible portion of the total tribal lands.

In addition to its sparse population, this area is at least 20 to 25 miles from areas with greater

than 1000 persons per square mile.7

Factor 4: Traffic and commuting patterns

These tribal areas have little population and commuting data indicates that the average

commuting time to work is 15-21 minutes. This data indicates that the average commuter from

these tribal areas does not commute daily to the San Diego area.

This area includes rural portions of Interstate 8; however, there is little traffic on these portions

of the highway compared to the San Diego area. Also, nearly all of this interstate is outside these

tribal lands and thus out of tribal jurisdiction.8

 5

 AQS 2001-2003.

6

 AQS 2001-2003.

7

 U.S. Census, 2000.
6-384

Factor 5: Expected growth (including extent, pattern and rate of growth)

These areas are separated from the urbanized portions of San Diego County by distance and

mountains. They are sparsely and lightly populated. There is no suburban or exurban growth on

these tribal lands and there is a separation of 20 to 25 miles from these tribal areas to areas with

population density of 1000 persons per square mile or greater. Because of this separation,

expansion of the San Diego area and suburbs will not impact these areas in the near future.

Because the population of these areas comprises such a small proportion of San Diego County as

a whole, growth of these areas would account for only a negligible portion of the overall growth

in San Diego County.9

Factor 6: Meteorology (weather/transport patterns)

[See discussion in Factor 1 for discussion of Meteorology (weather/transport patterns)]

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

These tribal areas are located 20 to 25 miles from the populated exurbs of San Diego. Within

those 20 to 25 miles are the Laguna Mountains. The presence of these mountains separate these

areas from the growing exurbs of the San Diego area. The elevations of the Laguna Mountains

are generally 3000 to 6000 feet, with the higher peaks immediately adjacent to these tribal lands.

These mountains form a barrier to air pollution and transport from the San Diego area to this

region. These areas are not a significant source of emissions within the county, but due to their

distance from the urbanized portions of San Diego County and the presence of the mountains

between the two, any effect on the urbanized areas of the county from emissions generated by

activities occurring on these tribal lands would be de minimis.

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

These tribal areas are outside the jurisdiction of the State of California and San Diego County.

Factor 9: Level of control of emissions sources

EPA does not believe that there are any sources of concern in these tribal areas. With no sources

of concern, the level of control in this area is not currently relevant and does not affect PM2.5 in

San Diego.

 8

 U.S. Census, “Profile of General Demographic Characteristics: 2000" (for Campo, Cuyapaipe, and Manzanita

Reservations; profile not available for La Posta Reservation, 2000.

9

 U.S. Census, 2000.
6-385

APPENDIX A

PM2.5 Design Values for San Diego and Imperial Counties

PM2.5 Design Values 10

note: all values are annual mean with units _g/m3

San Diego County

AQS ID LOCATION ANNUAL MEAN 2001-03

06-073-1002 Escondido 15.9 _g/m3

06-073-1007 San Diego-12th St. 15.9

06-073-0003 El Cajon 15.7

06-073-0001 Chula Vista 14.6

06-073-0006 San Diego-Overland 12.8

Imperial County

AQS ID LOCATION ANNUAL MEAN 2001-03

06-025-1003 El Centro 9.1

06-025-0005 Calexico 14.4 (incomplete data)

06-025-0003 Brawley 10.6 (incomplete data)

 10

 U.S. EPA, Air Quality Subsystem (AQS), 2001-2003
6-386

APPENDIX B

Description:

Southeastern San Diego County Unclassifiable/Attainment Areas

for the PM2.5 NAAQS

List of Areas: Campo unclassifiable/attainment areas #1 and #2, Cuyapaipe

unclassifiable/attainment area, La Posta unclassifiable/attainment areas #1 and #2, and

Manzanita unclassifiable/attainment area. 11

[Note: Longitude coordinates listed are in degrees west; Latitude coordinates are in degrees

north]

CAMPO Unclassifiable/attainment AREAS #1 AND #2

CAMPO Unclassifiable/attainment AREA #1

 Degrees Degrees

 Longitude Latitude

 -116.3938522 32.6008873

 -116.3938522 32.6021004

 -116.3938370 32.6023903

 -116.3938065 32.6084938

 -116.3938217 32.6146011

 -116.3938141 32.6168747

 -116.3937836 32.6211510

 -116.3938065 32.6246223

 -116.3938141 32.6250572

 -116.3938446 32.6293945

 -116.3938599 32.6313171

 -116.3938141 32.6434937

 -116.3938370 32.6458054

 -116.3938599 32.6528740

 -116.3938599 32.6603432

 -116.3938370 32.6705208

 -116.3937683 32.6748314

 -116.3937302 32.6833992

 -116.3937073 32.6893730

 -116.3891220 32.6893845

 11

 The boundaries for these designated areas are based on coordinates of latitude and longitude derived from EPA

Region 9’s GIS database and are illustrated in a map entitled “Southeastern San Diego County

Unclassifiable/Attainment Areas for the PM-2.5 NAAQS,” included in the Technical Support Document for the

2004 PM2.5 Designations. The map and this set of coordinates are available at EPA’s Region 9 Air Division office.

The designated areas roughly approximate the boundaries of the reservations for these tribes, but their inclusion in

this table is intended for Clean Air Act planning purposes only and is not intended to be a federal determination of

the exact boundaries of the reservations. Also, the specific listing of these tribes in this table does not confer, deny,

or withdraw Federal recognition of any of the tribes so listed nor any of the tribes not listed.
6-387

 -116.3851318 32.6893387

 -116.3819046 32.6893616

 -116.3761826 32.6893501

 -116.3758469 32.6892662

 -116.3734131 32.6892815

 -116.3683548 32.6892548

 -116.3672028 32.6892776

 -116.3624268 32.6892624

 -116.3624496 32.6958275

 -116.3625107 32.7037697

 -116.3624420 32.7122650

 -116.3623810 32.7183075

 -116.3623810 32.7192383

 -116.3623886 32.7198639

 -116.3624191 32.7258682

 -116.3624344 32.7294846

 -116.3624420 32.7343102

 -116.3610229 32.7343369

 -116.3530502 32.7343521

 -116.3438492 32.7343788

 -116.3372269 32.7344055

 -116.3266830 32.7344131

 -116.3175354 32.7343712

 -116.3093948 32.7343826

 -116.3092957 32.7306824

 -116.3092194 32.7265244

 -116.3106918 32.7265053

 -116.3115997 32.7265167

 -116.3116150 32.7219543

 -116.3116837 32.7182999

 -116.3116531 32.7167130

 -116.3116837 32.7110214

 -116.3117752 32.7053833

 -116.3117752 32.7037506

 -116.3117981 32.6973648

 -116.3118744 32.6903038

 -116.3119049 32.6893005

 -116.3183517 32.6893005

 -116.3274918 32.6892776

 -116.3325958 32.6892509

 -116.3326569 32.6920052

 -116.3326645 32.6923180

 -116.3333893 32.6923409

 -116.3339844 32.6923256

 -116.3360519 32.6923256

 -116.3398743 32.6923218
6-388

 -116.3409500 32.6923447

 -116.3409805 32.6901436

 -116.3410263 32.6892700

 -116.3452530 32.6892471

 -116.3511810 32.6892128

 -116.3511658 32.6824760

 -116.3511353 32.6747093

 -116.3511200 32.6681786

 -116.3511276 32.6616478

 -116.3511276 32.6602020

 -116.3511276 32.6548462

 -116.3511581 32.6485939

 -116.3511963 32.6456985

 -116.3512039 32.6400795

 -116.3511963 32.6340599

 -116.3511734 32.6310959

 -116.3511658 32.6280823

 -116.3511658 32.6251755

 -116.3511658 32.6250687

 -116.3511353 32.6204147

 -116.3510742 32.6167946

 -116.3511276 32.6139297

 -116.3511353 32.6067390

 -116.3511581 32.6043663

 -116.3629379 32.6033897

 -116.3682709 32.6029549

 -116.3682632 32.6114883

 -116.3682709 32.6169205

 -116.3741760 32.6169586

 -116.3758469 32.6170387

 -116.3843842 32.6170082

 -116.3852768 32.6169930

 -116.3852615 32.6113052

 -116.3852692 32.6029587

 -116.3852692 32.6024170

 -116.3852921 32.6020126

 -116.3852997 32.6016350

 -116.3921661 32.6010284

 -116.3938522 32.6008873

EXCLUDING:

 Degrees Degrees

 Longitude Latitude

 -116.3432693 32.6991501

 -116.3452988 32.6991692

 -116.3474503 32.6991806
6-389

 -116.3474350 32.7004051

 -116.3474579 32.7027702

 -116.3497925 32.7027740

 -116.3511810 32.7027893

 -116.3514023 32.7027893

 -116.3517685 32.7027740

 -116.3517227 32.7033768

 -116.3517151 32.7038116

 -116.3517075 32.7044868

 -116.3516922 32.7075272

 -116.3516846 32.7100334

 -116.3511581 32.7100220

 -116.3496399 32.7100334

 -116.3474045 32.7100410

 -116.3474121 32.7089043

 -116.3474197 32.7064056

 -116.3431625 32.7063751

 -116.3431473 32.7055168

 -116.3431702 32.7037964

 -116.3431931 32.7003136

 -116.3432007 32.6993828

 -116.3432693 32.6991501

CAMPO Unclassifiable/attainment AREA #2

 Degrees Degrees

 Longitude Latitude

 -116.4757996 32.6338768

 -116.4758072 32.6354027

 -116.4758301 32.6374321

 -116.4777145 32.6373940

 -116.4801788 32.6373405

 -116.4801559 32.6390724

 -116.4801559 32.6419983

 -116.4801559 32.6445580

 -116.4801865 32.6460190

 -116.4801788 32.6482124

 -116.4778137 32.6482468

 -116.4711609 32.6484070

 -116.4685593 32.6484604

 -116.4628830 32.6485977

 -116.4628677 32.6481361

 -116.4628983 32.6449471

 -116.4628830 32.6435204

 -116.4628677 32.6412926

 -116.4610519 32.6413460

 -116.4585495 32.6413803
6-390

 -116.4585419 32.6399918

 -116.4585495 32.6376915

 -116.4623947 32.6376266

 -116.4672012 32.6376038

 -116.4671707 32.6364365

 -116.4671631 32.6339645

 -116.4698563 32.6339149

 -116.4715118 32.6338959

 -116.4757996 32.6338768

CUYAPAIPE Unclassifiable/attainment AREA

 Degrees Degrees

 Longitude Latitude

 -116.3594589 32.8148613

 -116.3758469 32.8149872

 -116.3773727 32.8149681

 -116.3773575 32.8186951

 -116.3758545 32.8187332

 -116.3730850 32.8187523

 -116.3731766 32.8223953

 -116.3758469 32.8224297

 -116.3773727 32.8223877

 -116.3945618 32.8223038

 -116.3948517 32.8368340

 -116.4123306 32.8367386

 -116.4123688 32.8439903

 -116.4124451 32.8530045

 -116.4124527 32.8585320

 -116.4125443 32.8618469

 -116.4126282 32.8657188

 -116.4084244 32.8657303

 -116.4024582 32.8657722

 -116.3950500 32.8658104

 -116.3777466 32.8657455

 -116.3774643 32.8585205

 -116.3758469 32.8586006

 -116.3601303 32.8584747

 -116.3596268 32.8445740

 -116.3596115 32.8438034

 -116.3597107 32.8406830

 -116.3598175 32.8368759

 -116.3596649 32.8295746

 -116.3594971 32.8182030

 -116.3594589 32.8148613
6-391

EXCLUDING:

 Degrees Degrees

 Longitude Latitude

 -116.3774490 32.8331528

 -116.3817902 32.8331566

 -116.3818512 32.8404427

 -116.3775253 32.8404121

 -116.3774490 32.8331528

LA POSTA Unclassifiable/attainment AREAS #1 AND #2

LA POSTA Unclassifiable/attainment AREA #1

 Degrees Degrees

 Longitude Latitude

 -116.4124756 32.7194672

 -116.4124603 32.7229614

 -116.4124603 32.7262383

 -116.4124680 32.7283859

 -116.4124603 32.7296181

 -116.4124451 32.7304344

 -116.4123917 32.7310486

 -116.4122467 32.7324371

 -116.4121933 32.7330780

 -116.4121475 32.7335663

 -116.4121094 32.7337990

 -116.4120789 32.7339172

 -116.4119797 32.7340736

 -116.4119339 32.7342529

 -116.4119034 32.7344437

 -116.4118958 32.7346458

 -116.4119186 32.7357597

 -116.4119110 32.7375832

 -116.4073563 32.7376099

 -116.4073334 32.7377701

 -116.4073029 32.7429504

 -116.4073029 32.7447739

 -116.4031143 32.7447662

 -116.4030533 32.7484016

 -116.4019165 32.7483749

 -116.4008408 32.7483826

 -116.3992996 32.7483826

 -116.3983383 32.7483864

 -116.3969803 32.7483940

 -116.3963089 32.7483864

 -116.3946991 32.7483940

 -116.3935699 32.7484093
6-392

 -116.3924103 32.7484550

 -116.3907318 32.7484818

 -116.3884659 32.7485428

 -116.3858948 32.7486076

 -116.3828659 32.7486839

 -116.3806458 32.7487526

 -116.3797913 32.7487869

 -116.3791351 32.7488022

 -116.3774567 32.7488289

 -116.3774719 32.7461090

 -116.3758469 32.7461319

 -116.3734589 32.7461510

 -116.3734436 32.7488289

 -116.3675156 32.7488518

 -116.3610306 32.7488747

 -116.3609924 32.7480240

 -116.3610306 32.7452621

 -116.3734741 32.7452507

 -116.3734512 32.7415466

 -116.3669434 32.7415543

 -116.3609619 32.7415657

 -116.3610306 32.7411308

 -116.3610229 32.7343369

 -116.3624496 32.7343407

 -116.3624344 32.7294846

 -116.3624191 32.7258682

 -116.3623886 32.7198639

 -116.3708572 32.7197227

 -116.3758316 32.7196426

 -116.3784943 32.7196579

 -116.3839035 32.7196350

 -116.3875351 32.7196198

 -116.3911743 32.7196007

 -116.3941879 32.7195473

 -116.3970032 32.7195587

 -116.3989334 32.7195625

 -116.4012909 32.7195511

 -116.4023514 32.7195320

 -116.4040070 32.7195320

 -116.4072418 32.7195053

 -116.4124756 32.7194672
6-393

LA POSTA Unclassifiable/attainment AREA #2

 Degrees Degrees

 Longitude Latitude

 -116.4203491 32.7591209

 -116.4203339 32.7655792

 -116.4203262 32.7699738

 -116.4160233 32.7700539

 -116.4160538 32.7664719

 -116.4117279 32.7666054

 -116.4117584 32.7629204

 -116.4117889 32.7593193

 -116.4203491 32.7591209

MANZANITA Unclassifiable/attainment AREA

 Degrees Degrees

 Longitude Latitude

 -116.3610229 32.7343369

 -116.3610306 32.7411308

 -116.3609619 32.7415657

 -116.3607101 32.7415619

 -116.3605652 32.7415695

 -116.3605957 32.7435303

 -116.3606262 32.7452698

 -116.3610306 32.7452621

 -116.3609924 32.7480240

 -116.3610306 32.7488747

 -116.3610229 32.7496910

 -116.3609543 32.7500534

 -116.3608856 32.7587395

 -116.3608704 32.7631874

 -116.3608627 32.7672615

 -116.3609009 32.7709351

 -116.3564072 32.7709274

 -116.3466721 32.7708702

 -116.3436737 32.7708359

 -116.3390884 32.7708054

 -116.3270569 32.7707481

 -116.3264618 32.7707291

 -116.3184509 32.7708015

 -116.3171158 32.7707672

 -116.3171768 32.7670517

 -116.3171997 32.7631454

 -116.3172760 32.7569122

 -116.3173828 32.7511406

 -116.3173828 32.7501564
6-394

 -116.3173828 32.7500610

 -116.3174362 32.7489281

 -116.3234787 32.7489281

 -116.3266678 32.7488899

 -116.3266449 32.7416649

 -116.3266830 32.7344131

 -116.3372269 32.7344055

 -116.3438492 32.7343788

 -116.3530502 32.7343521

 -116.3610229 32.7343369

EXCLUDING:

 Degrees Degrees

 Longitude Latitude

 -116.3388977 32.7581825

 -116.3431778 32.7581978

 -116.3431625 32.7613106

 -116.3431625 32.7631645

 -116.3431320 32.7654572

 -116.3387756 32.7654266

 -116.3346558 32.7654114

 -116.3346634 32.7644844

 -116.3346558 32.7631302

 -116.3346634 32.7619247

 -116.3346710 32.7581978

 -116.3388977 32.758182
6-395

APPENDIX C

Map: Southeastern San Diego County Unclassifiable/Attainment Areas

for the PM2.5 NAAQS
6-356

6.9 Region 9 Nonattainment Areas

6.9.1 EPA 9-Factor Analyses for California for the Designation of PM2.5 Nonattainment

Areas

This attachment to the modification letter to California contains EPA’s preliminary evaluation of

the state’s recommended PM2.5nonattainment areas. The recommended areas have been

evaluated to determine if they follow the guidance provided in EPA’s memo of April 1, 2003,

“Designations for the Fine Particle National Ambient Air Quality Standards” from Jeffrey R.

Holmstead, Assistant Administrator of EPA to Region Administrators.

In the April 1, 2003 memo, EPA states that for the purposes of designating PM2.5 nonattainment

areas, it “presumes the entire MSA should be designated as nonattainment.” In areas where there

are multiple MSA’s comprising one larger CMSA, the entire CMSA is the presumptive

nonattainment area. This is based on the assumption that “violations of the PM2.5 NAAQS in

urban areas may be presumed attributable at least in part to contributions from sources

distributed throughout the Metropolitan Area.”

The April 1, 2003 memo also states that in some cases, a State or Tribe may find that a violation

of the PM2.5 standard is attributed to a significant metropolitan-scale component and yet believe

that the Metropolitan Area does not appropriately define the area that should be designated

nonattainment. EPA will consider requests for urban nonattainment area definitions that deviate

from OMB’s metropolitan area definitions on a case-by-case basis, considering the factors

described below:

Emissions in areas potentially included versus excluded from the nonattainment area

Air quality in potentially included versus excluded areas

Population density and degree of urbanization including commercial development in

included versus excluded areas

Traffic and commuting patterns

Expected growth (including extent, pattern and rate of growth)

Meteorology (weather/transport patterns)

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

Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

Level of control of emission sources

This attachment provides EPA’s preliminary conclusions on California’s recommended

PM2.5nonattainment areas with respect to EPA’s April 1, 2003 guidance and the nine factors

that must be considered when designating an area smaller than the Metropolitan Statistical Area.

California has recommended four PM2.5 nonattainment areas:

San Diego County

San Joaquin Valley

South Coast Air Basin

City Of Calexico, Imperial County, California
6-357

6.9.1.1 City of Calexico, Imperial County, California

There are three PM2.5 monitoring sites in Imperial County that are being used to determine this

area’s compliance with the NAAQS: Calexico - Ethel Street, El Centro, and Brawley. When the

State submitted their recommendations for PM2.5 nonattainment areas they used data from the

years 2000 through 2002. This data set indicated that the monitor at Calexico - Ethel Street was

in violation of the annual PM2.5 NAAQS, with a 3-year annual average of 15.6 _g/m3. The

2000-2002 three-year annual averages for El Centro and Brawley were 11.3 _g/m3 and 14.7

_g/m3, respectively.

When the 2003 data set became available, EPA recalculated the three-year annual averages for

these monitoring locations. The most recent three years of data (2001-2003) indicate that while

the three-year annual averages are close to the NAAQS, none of the sites exceed the annual

NAAQS of 15 _g/m3. The 2001-2003 year annual averages for Calexico, El Centro, and

Brawley are 14.3 _g/m3, 11.1 _g/m3, and 14.5 _g/m3 respectively.

It should be noted that the three monitoring sites did not have complete data sets for the 2001-

2003 timeframe. In order to calculate the annual averages, EPA used the data substitution

procedures in "Guideline on Data Handling Conventions for the PM NAAQS” (EPA-454/R-99-

008, 1999).

6.9.1.2 San Diego Area

For the San Diego area, California recommended San Diego County as the PM2.5 nonattainment

area. It includes the entire San Diego MSA.

The presumptive PM2.5 nonattainment area for San Diego is the San Diego MSA which includes

San Diego County in its entirety.

The state’s recommended PM2.5 nonattainment area is the same as EPA’s presumptive

nonattainment area.

Based on EPA’s preliminary nine-factor analysis of California’s recommendation, the

presumptive nonattainment area and all adjacent counties, EPA agrees that California’s

recommendation is an appropriate nonattainment area. We have included comments on each

factor in the pages following.

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment

area

The presumptive boundary for the San Diego MSA is all of San Diego County. The State of

California’s recommended PM2.5 nonattainment area includes all of San Diego County, under

the jurisdiction of the San Diego Air Pollution Control District. All potential emission sources in

the San Diego MSA are included in the State’s state recommended nonattainment area.
6-358

Adjacent counties to San Diego include Orange, Riverside, and Imperial Counties. Emissions

generated in Orange County and Riverside County are included in the state recommended South

Coast nonattainment area. Emissions originating in Imperial County do not contribute to

elevated PM2.5 concentrations in San Diego County because Imperial County is separated from

the San Diego area by the Laguna Mountains and many miles of desert.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 2: Air quality in potentially included versus excluded areas

The State’s recommended boundary includes all violating monitoring sites. Violating monitors

in Orange County and Riverside County are included in the state-recommended South Coast

nonattainment area. There are no monitors in Imperial County that are currently in violation of

the either the 24-hour or annual PM2.5 NAAQS.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

All urbanized areas in the San Diego MSA are included in the state’s recommended boundary

and exist west of the Laguna Mountains, which bisect San Diego County from the north to the

south. Urbanized areas in the adjacent counties of Orange and Riverside fall within the South

Coast nonattainment area. The nearest urbanized area in Imperial County is the El Centro area

which is separated from the San Diego area by the Laguna Mountains and many miles of desert.

The El Centro area is currently not violating either the 24-hour or annual PM2.5 NAAQS.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 4: Traffic and commuting patterns

California’s recommended PM2.5 nonattainment area, San Diego County, contains most of the

VMT for the San Diego MSA. The amount of commuting traffic between San Diego and

Orange or Riverside Counties is minimal and would not contribute significantly to air quality

problems in San Diego County.

Because of the great distance between San Diego is urbanized areas and Imperial County, traffic

and commuting patterns in Imperial County do not contribute to air quality violations in San

Diego County.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.
6-359

Factor 5: Expected growth (including extent, pattern and rate of growth)

Expected growth in the San Diego MSA will be contained in San Diego County. Expected

growth in the adjacent counties of Orange and Riverside will be accounted for in the staterecommended South Coast nonattainment area. Growth in urban areas of Imperial County will

not impact the San Diego MSA due to the great distance between these areas.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 6: Meteorology (weather/transport patterns)

The distribution of high PM2.5 concentrations within the San Diego area appear to be dependent

upon calm-to-light winds and not as dependent upon wind direction. This suggests, as in the

South Coast area, that there is enough activity within the San Diego area to generate high PM2.5

concentrations under many conditions and that high concentrations are not being caused by

adjacent areas such as Orange, Riverside and Imperial Counties.

Because high PM2.5 concentrations occur during periods of calm-to-light wind conditions, the

source of the high PM2.5 concentrations is likely within San Diego County itself. Under these

conditions, it is unlikely that transport is bringing precursors into the County in levels significant

enough to cause violations there.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

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

The San Diego MSA is bounded by the Laguna Mountains to the east, which bisect San Diego

County into a western portion, where the San Diego MSA is located, and an eastern portion

which is rural and adjacent to Imperial County. To the west is the Pacific Ocean. Orange and

Riverside counties are to the north and the U.S.-Mexico border forms the southern boundary.

Emissions originating in Imperial County do not contribute to elevated PM2.5 concentrations in

San Diego County because Imperial County is separated from the San Diego area by the Laguna

Mountains and miles of desert. While there could be some transport of emissions from Orange

or Riverside counties, these areas are included in the state-recommended South Coast

nonattainment area. Any emissions emanating from across the U.S.-Mexico border will need to

be dealt with through the planning process.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.
6-360

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

The state recommended San Diego County nonattainment area is entirely under the jurisdiction

of the San Diego Air Pollution Control District. To the north of San Diego County is Orange

and Riverside Counties, which are included in the state-recommended South Coast

nonattainment area. Imperial County to the east is under the jurisdiction of the Imperial County

Air Pollution Control District. Imperial County contributes minimally if at all to PM2.5 air

quality in San Diego County because of the distance between the San Diego urban area and

Imperial County and the Laguna Mountain range which effectively separates the San Diego

urban area from Imperial County.

EPA concludes that analysis of this factor supports designating San Diego County as the

nonattainment area for the San Diego Metropolitan Area.

Factor 9: Level of control of emissions sources

Imperial County does not contribute to violations in San Diego County because of the low level

of emissions in the western half of Imperial County, the intervening mountains (extending to

over 4000 ft. in height), and the prevailing westerly winds. There is no significant commute

pattern linking the two areas, since the urbanized portions of San Diego and Imperial County are

separated by more than 100 miles of relatively sparsely populated mountains and desert (the

highway distance from San Diego to El Centro is 117 miles). The two counties are under

separate air quality jurisdictions (San Diego County Air Pollution Control District and Imperial

County Air Pollution Control District) and in separate State air basin planning areas (San Diego

Air Basin and Salton Sea Air Basin). While the coastal portion of San Diego County is highly

urbanized with a population of approximately 3,000,000, the entire Imperial County is rural and

primarily agricultural, with a total County population of approximately 150,000 (population

density of 35 per square mile). San Diego’s average daily VMT is over 75,000,000, compared to

Imperial County’s average daily VMT of approximately 4,215,000.

6.9.1.3 San Joaquin Valley Area

For the San Joaquin Valley, California recommended the San Joaquin Valley (SJV) as the PM2.5

nonattainment area.

This area includes the SJV Air Basin portion of Kern County, and all of Fresno, Kings, Madera,

Merced, San Joaquin, Stanislaus and Tulare counties.

The presumptive nonattainment area includes the MSA’s that have violations of the PM2.5

NAAQS. These include the following MSA’s: Bakersfield (Kern County), Fresno (Fresno

County), Merced (Merced County), Modesto (Stanislaus County), and Visalia-Tulare-Porterville

(Tulare County).

The only portion of the presumptive nonattainment area excluded from the state’s SJV

recommendation is Eastern Kern County (EKC), which is in a separate air basin (Mojave Desert)
6-361

and is separated from the SJV by the Sierra Nevada and Tehachapi Mountains and significant

distance.

The seventeen counties adjacent to the presumptive area and excluded from the state’s

recommendation (Alameda, Amador, Calaveras, Contra Costa, Inyo, Los Angeles, Mariposa,

Mono, Monterey, Sacramento, San Benito, San Bernardino, San Luis Obispo, Santa Barbara,

Santa Clara, Tuolumne, Ventura) are not in the SJV. These areas are either mountainous,

separated from SJV by mountains, separated from SJV by significant distance or a combination

of all of three. Thus, this indicates that these counties should not be included in the San Joaquin

Valley nonattainment area.

Based on the following nine-factor analysis, EPA concurs with the State’s recommendation to

include San Joaquin and Kings counties and to exclude that portion of Kern County east of the

Tehachapi and Sierra Nevada Mountains. The excluded portion of Kern County is a rural, desert

area in a separate State air basin (Mojave Desert) from the San Joaquin Valley (SJV). We have

included comments on each factor in the pages following.

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment

area
6-362

The EKC emissions are a tiny fraction of SJV emissions, as shown in the table below.

Comparison of PM2.5 and PM2.5 Precursor Emissions

Eastern Kern County vs. San Joaquin Valley

Source: California Air Resources Board,

2004 California Almanac of Emissions & Air Quality,

2003 Estimated Annual Average Emissions in Tons per Day

VOC NOx SO2 PM2.5

Eastern Kern County 13.2 37.9 3.9 9.5

San Joaquin Valley 396.7 504.9 26.6 150.5

California’s recommended PM2.5nonattainment area only excludes the EKC which contributes

only a tiny fraction of the emissions in the presumptive nonattainment area. This excluded area

is separated from the SJV by the Tehachapi and Sierra Nevada mountains. Thus, the excluded

area does not cause violations of the NAAQS in the SJV.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the San Joaquin Valley nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 2: Air Quality in potentially included versus excluded areas

California’s recommended PM2.5 nonattainment area, the SJV, contains all violating monitors.

Thus, violations are not occurring in the excluded portions of the metropolitan statistical area.

With respect to adjacent counties, the only monitors that violate the NAAQS in an adjacent

county are in counties that have been recommended as part of the Los Angeles nonattainment

area and are separated from the SJV by mountains.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

The population of the EKC is approximately 120,000, compared to the SJV population of

approximately 3,500,000. EKC has a very low population density (47 per square mile), degree

of urbanization, and projected population growth, since the major source of EKC employment is

the military.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the San Joaquin Valley by topography and/or distance. Based on their location
6-363

and this factor, these counties should not be included in the San Joaquin Valley nonattainment

area.

EPA concludes that analysis of this factor supports designating the San Joaquin Valley as the

nonattainment area for PM2.5.

Factor 4: Traffic and commuting patterns

Average daily VMT for EKC is approximately 4,200,000 compared to SJV VMT of

approximately 85,000,000. There is an insignificant volume of daily commute traffic between

EKC and SJV.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 5: Expected growth (including extent, pattern and rate of growth)

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 6: Meteorology (weather/transport patterns)

There are typically westerly winds in the southern SJV, which have the potential to carry some

levels of PM2.5 precursors from SJV to EKC, although the mountains (elevations from 4,064 ft.

at the Tehachapi Pass in the south to 9,875 ft. at Sunday Peak in the north) serve as a barrier to

transport. Attainment of the PM2.5 and 8-hour ozone NAAQS within SJV will require adoption

of Statewide and SJV controls at a level of stringency sufficient to ensure that transport from

SJV to EKC will be further minimized. Transport from EKC to SJV is insignificant, because of

the high mountains, the prevailing wind direction, and the insignificant level of emissions in

EKC.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.
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Factor 7: Geography/topography (mountain ranges or other air basin boundaries)

California’s recommended PM2.5 nonattainment area, the SJV, is bounded on the west by the

Coast Ranges, on the south by the Tehachapi mountains, and on the east by the Sierra Nevada

mountains. These mountains act as a barrier to pollution. Violations of the PM2.5 NAAQS are

not caused by areas outside the SJV.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

The EKC is excluded from the SJV nonattainment area because it is under the jurisdiction of the

Kern County Air Pollution Control District, and in a separate air basin, The Mojave Desert Air

Basin. SJV nonattainment areas are in the same separate air basin and are all under the

jurisdiction of the SJV Unified Air Pollution Control District. The California Air Resources

Board coordinates Statewide planning, oversees implementation of intra-state planning

requirements (including transport mitigation), and coordinates inter-basin planning, to the extent

necessary.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.

Factor 9: Level of control of emissions sources

Both EKC and SJV are designated nonattainment for the 8-hour ozone NAAQS (with the

exception of the extreme northeastern corner of EKC, which is designated attainment). Control

measures developed to attain the 8-hour ozone NAAQS in both the EKC and SJV will likely

focus on coordinated State initiatives to reduce precursor emissions from mobile sources. The

State also is aggressively pursuing Statewide controls on primary PM emitted by mobile sources

as part of a diesel risk reduction initiative.

Counties adjacent to the presumptive area and excluded from the state’s recommendation are

separated from the SJV by topography and/or distance. Based on their location and this factor,

these counties should not be included in the SJV nonattainment area.

EPA concludes that analysis of this factor supports designating the SJV as the nonattainment

area for PM2.5.
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6.9.1.4 South Coast Air Basin Area

For the Los Angeles nonattainment area, California recommended the South Coast Air Basin as

the PM2.5 nonattainment area. This area includes the South Coast Air Basin portions of Los

Angeles, Orange, Riverside and San Bernardino counties.

The presumptive nonattainment area is the Los Angeles CMSA, which includes the counties of

Los Angeles, Orange, Riverside, San Bernardino and Ventura.

Based on EPA’s preliminary nine-factor analysis of California’s recommendation, the

presumptive nonattainment area and all adjacent counties, EPA agrees that California’s

recommendation is an appropriate nonattainment area for the Los Angeles area (note: The “Los

Angeles” area consists of the urban areas of the city of Los Angeles and surrounding developed

areas within the Los Angeles basin). We have included comments on each factor in the pages

following.
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6-367
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Factor 1: Emissions in areas potentially included versus excluded from the nonattainment area

PM SO2 NOX VOC Amm Carbon Crustal SO2 - Ex Pt NOx - Ex Pt

LScore

Cumulative 

L-Score

C/MSA Total 69,872 22,119 530,780465,495 61,094 41,151 23,840 10,900476,347

C A Los Angeles 28,855 16,629 276,002251,469 14,252 19,365 7,097 7,460254,66853.4 53.4

C A San Bernardino 17,741 3,246 109,488 50,278 21,541 8,147 8,022 1,602 81,59719.7 73.1

C A Orange 8,585 1,129 73,846 89,987 7,330 5,714 2,466 974 71,37412.7 85.8

C A Riverside 10,476 674 52,809 46,232 16,164 5,280 4,921 575 51,31510.0 95.8

C A Ventura 4,215 441 18,635 27,529 1,807 2,645 1,334 289 17,393 4.2 100.0

NV Clark 13,408 48,089 76,295 50,366 2,362 3,897 8,880 4,583 45,59440.5

CA Kern 13,712 5,468 71,174 41,469 11,496 7,469 5,296 1,651 54,60416.5

CA San Diego 12,683 2,007 76,341 95,358 6,015 7,297 4,827 1,748 73,04614.8

CA Santa Barbara 4,201 1,301 14,919 24,755 2,032 2,764 1,292 280 13,355 4.5

CA Imperial 4,931 264 16,683 11,254 8,473 2,151 2,523 195 15,887 3.6

AZ Mohave 3,037 695 12,691 12,837 1,231 2,021 959 688 11,935 3.3

CA Inyo 2,764 394 1,694 3,247 747 2,133 564 173 1,424 2.0

AZ La Paz 810 142 3,100 2,407 503 319 483 142 3,062 0.7

Area Total 125,418 80,479 803,677 707,188 93,953 69,202 48,664 20,360 695,254

ST COU Total Emissions, 2001 (tons)

Weighted 

Emisssions
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2003 Estimated Non-Natural Emissions (tons per day)

County South Coast Air Basin

portion of Los Angeles CMSA

(area included in nonattainment area)

non-South Coast Air Basin

portion of Los Angeles CMSA

(area excluded from nonattainment

area)

 Emissions

(included area)

Emissions

(excluded area)

ROG* NOX SOX PM2.5 ROG* NOX SOX PM2.5

Los Angeles 480.80 630.10 52.00 55.90 20.90 26.90 0.60 8.90

(As a

percentage)

48.8% 48.0% 71.5% 34.7% 2.1% 2.0% 0.8% 5.5%

Orange 159.40 174.10 6.90 17.80

(As a

percentage)

16.2% 13.3% 9.5% 11.0%

Riverside 79.00 125.00 1.90 16.00 17.20 29.90 0.40 7.40

(As a

percentage)

8.0% 9.5% 2.6% 9.9% 1.7% 2.3% 0.6% 4.6%

San

Bernardino

85.00 115.50 2.20 16.00 87.30 160.90 7.40 28.40

(As a

percentage)

8.6% 8.8% 3.0% 9.9% 8.9% 12.3% 10.2% 17.6%

Ventura (land

area)

54.71 50.75 1.31 10.80

(As a

percentage)

5.6% 3.9% 1.8% 6.7%

Total 804.20 1044.70 63.00 105.70 180.11 268.45 9.71 55.50

(As a

percentage)

81.7% 79.6% 86.6% 65.6% 18.3% 20.4% 13.4% 34.4%

*(excluding non-anthropogenic, aka “natural” emissions)

ROG is defined as “Reactive Organic Gas”

Factor 1 (continued): Emissions in areas potentially included versus excluded from the

nonattainment area

In the review of this factor, data from EPA’s Emission Inventory and California Air Resources

Board (CARB) has been used. This data is displayed in Figures 1.1 and 1.2. The CARB data

was useful because it allowed calculation of included and excluded areas’ emission inventories.

Also, EPA produced a weighted emission index, referred to as an “L-score” for each county,

which is another method of examining emission levels in various counties.

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, contains most

of the anthropogenic emissions in the Los Angeles CMSA. The only excluded areas with

significant emissions are population centers (Palm Springs, Lancaster-Palmdale and VictorvilleApple Valley-Hesperia) significantly north or east of Los Angeles. These areas are separated

from the Los Angeles area by the San Gabriel, San Bernardino and San Jacinto mountain ranges,
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which contain the Los Angeles PM2.5 problem to the Los Angeles area. It is not a problem in

the excluded areas and prevailing winds in the excluded areas are generally away from the Los

Angeles area. Thus, emissions in the excluded areas are not causing or contributing to violations

in the Los Angeles area.

The other excluded area is Ventura County, which produces a small portion of the emissions in

the Los Angeles CMSA. Most of the development and population in Ventura County is located

away from the Los Angeles area and much of the county is separated from the Los Angeles area

by mountains.

Six counties adjacent to the Los Angeles CMSA (Clark, NV; Imperial, CA; Inyo, CA; La Paz,

AZ; Mohave, AZ; and Santa Barbara, CA) are separated from the Los Angeles area by great

distance, mountain ranges, desert or a combination of all three. Thus, this indicates that these

counties should not be included in the Los Angeles nonattainment area.

Two counties adjacent to the Los Angeles CMSA are in separate nonattainment areas (e.g., Kern,

San Diego) and are separated from the Los Angeles area by mountain ranges. Thus, they are not

included in the Los Angeles nonattainment area for those reasons.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

Factor 2: Air Quality in potentially included versus excluded areas

C/MSA Total 27.4 N A 28.9 N A 29.8 N A

C A Los Angeles 22.8 N A 24.4 N A 25.9 N A

C A San Bernardino 24.5 N A 25.9 N A 25.8 N A

C A Orange 18.6 N A 20.3 N A 22.4 N A

C A Riverside 27.4 N A 28.9 N A 29.8 N A

C A Ventura 14.5 A 14.8 A 14.5 A

NV Clark 11.0 A 10.9 A 11.0 A

CA Kern 21.8 NA 22.8 NA 23.7 NA

CA San Diego 15.9 NA 16.4 NA 17.1 NA

CA Santa Barbara 9.5 A 9.9 A 13.0 a

CA Imperial 9.1 A 15.6 NA 15.7 NA

AZ Mohave 

CA Inyo 6.2 A 7.8 a 7.6 a

AZ La Paz 

Area Total 27.4 NA 28.9 NA 29.8 NA

'01-'03 '00-'02 '99-'01

ST COU

Design Values

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, contains all

violating monitors of the Los Angeles CMSA. Thus, violations are not occurring in the excluded
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portions of the metropolitan area. With respect to adjacent counties, the only monitor that

violates in an adjacent county is in Kern County which will be part of the SJV nonattainment

area. This area is separated from the Los Angeles area by two mountain ranges.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

Population and Population Density

County South Coast Air Basin

portion of Los Angeles CMSA

(area included in nonattainment area)

non-South Coast Air Basin

portion of Los Angeles CMSA

(area excluded from nonattainment area)

 Population

(included area)

Population

Density

(included area)

Population

(excluded area)

Population Density

(excluded area)

Los Angeles *9,222,000 *3,693 *298,000 *190

Orange 2,846,289 3,607 --- ---

Riverside *1,199,000 *544 *347,000 *68

San Bernardino *1,330,000 *1,057 *379,000 *20

Ventura --- --- 753,197 425

Total *14,596,289 *2,164 *1,777,000 *65

Source: U.S. Census, 2000

*figure based on estimate of partial county population and/or population density

California’s recommended nonattainment area has a population density of 2164 persons per

square mile. The excluded portion of the Los Angeles C/MSA has a population density of 65

persons per square mile. The recommended nonattainment area contains the densely populated

portions of the Los Angeles C/MSA. It also contains 89% of the C/MSA’s population.

Furthermore, the excluded areas consist of areas separated from the included areas by

topography and/or sparsely populated deserts.

Counties adjacent to the C/MSA are separated from the Los Angeles area by deserts and great

distance and are not included in the nonattainment area for that reason.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.
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Factor 4: Traffic and commuting patterns

Vehicle Miles Traveled

County South Coast Air Basin

portion of Los Angeles CMSA

(area included in nonattainment area)

Non-South Coast Air Basin

portion of Los Angeles CMSA

(area excluded from nonattainment

area)

Average Daily

Vehicle Miles

Traveled

(included area)

VMT as a

percentage of

 LA CMSA

(included area)

Average Daily

Vehicle Miles

Traveled

(excluded area)

VMT as a

percentage of

 LA CMSA

(excluded area)

Los Angeles 179,875,902 47.5 3,935,115 1.0

Orange 67,855,304 17.9 --- ---

Riverside 37,266,851 9.8 18,478,676 4.9

San Bernardino 35,448,320 9.4 17,872,337 4.7

Ventura --- --- 18,215,281 4.8

Total 320,446,377 84.6 58,501,409 15.4

Appendix C: Surface Area, Population, and Average Daily Vehicle Miles Traveled.

California’s recommended PM2.5nonattainment area, the South Coast Air Basin, contains most

(84.6%) of the Vehicle Miles Traveled (VMT) for the Los Angeles C/MSA.

Other portions of the Los Angeles C/MSA outside the South Coast Air Basin account for 15.4%

of the VMT for the Los Angeles CMSA. The areas outside the South Coast Air Basin in Los

Angeles, Riverside and San Bernardino counties account for 10.6% of the VMT in the Los

Angeles CMSA, however, these areas are, for the most part, only sparsely populated desert areas

separated from the Los Angeles area by the San Gabriel, San Bernardino, and San Jacinto

Mountains. The area outside the South Coast Air Basin in Ventura County accounts for 4.8% of

the VMT in the Los Angeles CMSA. Most of the population in Ventura County is in the

Ventura-Oxnard area. We believe that the distribution of VMT in Ventura County is similar to

population, and thus that most of the VMT in Ventura County is in the Ventura-Oxnard area.

This area is approximately 35 miles from the nearest violating monitor in the Los Angeles area

and is separated from the Los Angeles area by the Santa Monica Mountains and Simi Hills and

thus does not contribute to violations in the Los Angeles area. The Ventura County community

closest to Los Angeles county is Simi Valley; however, its population is only 15% of the entire

county and is separated from the Los Angeles area by the Santa Susana mountains, Simi Hills

and other topography in the area. We believe that a similarly small proportion of Ventura

County VMT is in Simi Valley. Based on VMT data for Ventura County, we believe that this

factor does not show that Ventura areas are causing violations in the Los Angeles area.

There are several counties adjacent to the Los Angeles CMSA (Clark, NV; Imperial, CA; Inyo,

CA; Kern, CA; La Paz, AZ; Mohave, AZ; Santa Barbara, CA; San Diego, CA). None of these

counties will be included in the Los Angeles nonattainment area based on this factor because
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these areas are too distant from the Los Angeles area, there is little, if any, commuting to the Los

Angeles area from these counties, and they are separated by geography from the Los Angeles

area. With respect to this factor, these areas do not cause or contribute to violations in the Los

Angeles area.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.
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Factor 5: Expected growth (including extent, pattern and rate of growth)

2002 Area (sq 

miles)

Density 

'02

Growth '90-

'00

Pct 

chng '90-

'00

1990 2000 Growth 

'02-'10

Pct chng 

'02-'10

C/MSA Total 17,044,188 33,966 502 1,842,116 1 3 14,531,52916,373,6451891964 1 1

C A Los Angeles 9,806,577 4,060 2,415 656,174 7 8,863,1649,519,338 797875 8

C A San Bernardino 1,816,072 20,062 9 1 291,054 2 1 1,418,3801,709,434 371735 2 0

C A Orange 2,938,507 790 3,720 435,733 1 8 2,410,5562,846,289 225269 8

C A Riverside 1,699,112 7,208 236 374,974 3 2 1,170,4131,545,387 426425 2 5

C A Ventura 783,920 1,846 425 84,181 1 3 669,016 753,197 70660 9

NV Clark 1,522,164 7,911 192 634,306 86 741,459 1,375,765 447184 29

CA Kern 694,059 8,142 85 118,168 22 543,477 661,645 165759 24

CA San Diego 2,906,660 4,205 691 315,817 13 2,498,016 2,813,833 534776 18

CA Santa Barbara 403,084 2,739 147 29,739 8 369,608 399,347 65373 16

CA Imperial 146,248 4,175 35 33,058 30 109,303 142,361 75337 52

AZ Mohave 165,593 13,312 12 61,535 66 93,497 155,032 28810 17

CA Inyo 18,214 10,192 2 -336 -2 18,281 17,945 1233 7

AZ La Paz 19,517 4,500 4 5,871 42 13,844 19,715 5579 29

Area Total 22,919,727 89,142 257 3,040,274 16 18,919,01421,959,2883216015 14

Population & Area Additional Population Info

ST COU
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California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, contains most

of the expected growth for the Los Angeles C/MSA. The areas in the Los Angeles C/MSA

experiencing the greatest population growth during the 1990's were Riverside and San

Bernardino counties with growth rates of 21% and 32% respectively. This high rate of growth is

expected to continue in these counties. The recommended nonattainment area contains the

portions of these counties on the edge and beyond the Los Angeles suburbs, so likely growth and

expansion of the populated areas will occur within the recommended nonattainment area.

Ventura County is outside the recommended area, but inside the Los Angeles C/MSA. Ventura’s

growth rate is projected to be 9% through 2010 compared to the slowest growth areas, Los

Angeles and Orange counties where growth rates of 8% are projected. Furthermore, Simi

Valley, the area of Ventura in closest proximity to Los Angeles, has experienced a slowing of

growth and appears to be largely built out. Thus, we do not expect high rates of growth in this

area either.

Some counties adjacent to the C/MSA have high rates of growth and/or are projected to;

however, these counties are separated from the Los Angeles area and its suburbs by some or all

of the following: great distances, mountain ranges, deserts and sparsely populated areas and thus

do not contribute or cause violations in the Los Angeles area.

Based on analysis of this factor, the recommended area includes the Los Angeles area and nearby

areas of expected growth, so the recommended area is appropriate. EPA concludes that analysis

of this factor supports designating the South Coast Air Basin as the nonattainment area for the

Los Angeles Metropolitan Area.

Factor 6: Meteorology (weather/transport patterns)

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, experiences

high PM2.5 concentrations throughout the area and these concentrations may occur any time of

year. Generally, the highest concentrations occur when winds are light and the atmosphere is

stable.

Based on an analysis of wind strength and direction associated with PM2.5 concentrations, high

concentrations are found throughout the South Coast Air Basin, and they tend to occur when

winds are light, especially when the average wind speed is below 4 mph. At most monitors, high

PM2.5 concentrations can occur regardless of the wind direction; in fact, most monitors have a

bi-modal distribution of high PM2.5 concentrations with respect to wind direction. Most of these

monitors have the same bi-modal distribution of average winds as well, generally from the west

to northwest and also from the southeast. It appears that calm to light winds are a more

important factor than the direction from which those winds originate.

The abundance of sources in the South Coast Air Basin and widespread distribution of high

PM2.5 concentrations, dependent upon calm-to-light winds and not as dependent upon wind

direction suggests that there is enough activity within the basin to generate high PM2.5

concentrations under many conditions and that high concentrations are not being caused by

adjacent areas.
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Because mountains nearly surround the South Coast Air Basin, and high PM2.5 concentrations

occur during periods of calm-to-light wind conditions, the source of the high PM2.5

concentrations is likely within South Coast Air Basin itself. Under these conditions, it is

unlikely that transport is bringing precursors into the basin in levels significant enough to cause

violations there.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

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

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, is bounded on

the southwest by the Pacific Ocean, on the west by the Santa Monica, Santa Susana Mountains

and Simi Hills, on the north by the San Gabriel Mountains, on the northeast by the San

Bernardino, on the east by the San Jacinto Mountains and on the south by the Santa Ana and

coast range mountains. These hills and mountain ranges have elevations of 2,000 to well over

10,000 feet and act as barriers to pollution. Thus, violations in the Los Angeles area are not

caused or contributed to by areas outside the South Coast Air Basin.

The excluded areas of the Los Angeles CMSA are separated from the Los Angeles area by the

aforementioned mountains and also great distances, and/or deserts.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

The five counties of the Los Angeles CMSA comprise 33,954 square miles. This area is

equivalent to a square that is 184 miles long and 184 miles wide. The Los Angeles metropolitan

and urbanized areas, although large, are only a small fraction of the entire Los Angeles CMSA,

however, since Los Angeles’ development occupies small portions of the area’s very large

counties, especially Riverside, San Bernardino and Ventura counties, and because CMSA’s are

comprised of units no smaller than counties (except in New England), this CMSA is much larger

than the Los Angeles area. Although this is the presumptive nonattainment area, it is much

larger than the Los Angeles area. Furthermore, it is much larger than the area with PM2.5

NAAQS violations and its accompanying source areas.

The CMSA encompasses fully five different counties, four different local air districts, coastal

regions, alpine mountain regions as well as both low and high deserts.

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, is under the

jurisdiction of the South Coast Air Quality Management District and includes Los Angeles and

its adjacent urban areas, including those in other counties.
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The other air districts within the Los Angeles C/MSA are separate agencies that due to

geography and distance from Los Angeles, are not included in the Los Angeles nonattainment

area.

To the west of the South Coast Air Basin is the Ventura County Air Pollution Control District,

which has been a separate air quality planning entity, with its own board of elected officials and

distinct responsibilities for all air quality planning, regulatory development, enforcement, and

public participation activities, with the exception of those programs that are conducted under the

jurisdiction of a State agency (mobile source standards, consumer products, pesticides, motor

vehicle inspection and maintenance, etc.). Because of the long history of effective statewide

planning and independent agency planning and because of differences in structure and approach

between the air pollution control boards of the Ventura and South Coast, it is likely that

compelling the two areas to share jurisdictional responsibility for air quality planning in an

expanded nonattainment area would interfere with, rather than promote, harmonious and

efficient air quality planning. Ventura County, although given an attainment designation for

PM2.5, would nonetheless continue its efforts to reduce direct and indirect emissions, as

explained further in the analysis of Factor 9.

To the northeast of South Coast Air Basin are the Antelope Valley Air Pollution Control District

and the Mojave Desert Air Quality Management District. These areas, although part of the Los

Angeles CMSA, are separated from the Los Angeles area by the San Gabriel and San Bernardino

mountain ranges, which have elevations over 10,000 feet. For that reason, these areas should not

be included in the Los Angeles nonattainment area.

Moreover, the South Coast AQMD has a long history of analyzing and addressing existing and

potential transport problems affecting downwind jurisdictions. Finally, coordinated rule

development and transport mitigation occurs throughout California because of various provisions

of the California Clean Air Act and subsequent legislation, along with the activities of the

California Air Pollution Control Officers Association.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.

Factor 9: Level of control of emissions sources

California’s recommended PM2.5 nonattainment area, the South Coast Air Basin, has an extreme

designation for the 1-hour ozone standard. It has also been designated ‘severe-17’ for the 8-hour

ozone standard. The area has some of the most stringent controls in the nation.

This factor is not relevant for other Los Angeles C/MSA areas in the Mojave Desert because they

are separated from the Los Angeles area by mountains.

Ventura County is also in large part, separate from the Los Angeles area by topography and

distance, with just one community near Los Angeles County (although this area, Simi Valley, is

also separated from Los Angeles by a mountain pass). Nevertheless, the level of control of

emissions sources in Ventura County is already high and expected to become more stringent,
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even without a nonattainment designation in Ventura County. The nature of this control is

summarized below:

(1) Ventura County APCD and South Coast AQMD already have a very high level of control of

PM precursor emissions, and the agencies are undertaking further progressive control strategy

development activities to achieve further control as needed to attain and maintain the NAAQS.

(2) Although it is not proposed to be designated nonattainment for the federal PM2.5 NAAQS,

Ventura is designated nonattainment for the extremely stringent California PM10 NAAQS and

must therefore pursue feasible controls to reduce PM concentrations.

(3) The County is also classified as a moderate nonattainment area for the Federal 8-hour ozone

NAAQS. Since the two principal ozone precursors are also PM precursors in Ventura, the

Ventura County APCD must continue to pursue stringent controls of NOx and VOC in order to

attain the 8-hour ozone NAAQS and these controls will benefit PM concentrations.

(4) A large part of the PM precursors are under the State's jurisdiction, and the involved State

agencies are planning to adopt additional stringent emission controls on a Statewide basis.

(5) Attaining the PM2.5 NAAQS is expected to require the South Coast AQMD and the State to

adopt a level of emissions control far in excess of what would be needed to ensure continued

maintenance in Ventura County.

Thus, designating Ventura County as part of the South Coast PM2.5 nonattainment area is not

likely to affect the level of emissions control applicable in the area or upwind in the South Coast.

EPA concludes that analysis of this factor supports designating the South Coast Air Basin as the

nonattainment area for the Los Angeles Metropolitan Area.
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6.9.2 Justifications for Changes to EPA Recommendations Contained in the June 29,

2004 Letters to States

TECHNICAL SUPPORT DOCUMENT

U.S. EPA Region 9

Unclassifiable/Attainment Designation

for

Certain Areas in Southeastern San Diego County

for

The PM2.5 NAAQS

Includes the Tribal Areas of The:

Campo Band of Kumeyaay Indians

Cuyapaipe Band of Kumeyaay Indians

La Posta Band of Mission Indians

and

Manzanita Tribal Lands
6-380

Southeastern San Diego County Unclassifiable/Attainment Areas for the PM2.5 NAAQS:

Southeastern San Diego County Indian Reservations

[Note: The non-tribal areas in the vicinity of the designated unclassifiable/attainment areas are

under California’s jurisdiction and are part of a county-based area that we are designating as

nonattainment. The State of California recommended designating all of San Diego County as a

single PM2.5 nonattainment area. This recommendation is consistent with presumptions that

follow our guidance on designating PM2.5 nonattainment areas. EPA agrees with the State of

California’s recommendation.]

This section applies to the portion of San Diego County listed below1:

La Posta Areas #1 and #2

Cuyapaipe Area

Manzanita Area

Campo Areas #1 and #2

The four tribes that occupy these six areas did not submit recommendations to EPA.

These areas, which approximate the boundaries of the reservations of the four Tribes in

southeastern San Diego County, are designated unclassifiable/attainment. Based on their

location and other factors, we have determined that these areas do not violate the PM2.5 National

Ambient Air Quality Standards (NAAQS). We also believe that these areas do not contribute to

PM2.5 in other areas.

Although the areas are surrounded by a countywide nonattainment area, the United States has a

unique legal relationship with tribal governments which derives from the United States

Constitution, treaties, statutes, Executive Orders and court decisions, and is commonly referred

to as the Federal government’s trust relationship with Tribes. Guidelines for EPA’s role in this

relationship are outlined in the EPA Policy for the Administration of Environmental Programs on

Indian Reservations (“1984 Indian Policy”) which was issued in 1984 and has been reaffirmed

by successor administrations.

The 1984 Indian Policy states that in the course of protecting human health and the environment,

EPA should recognize tribal governments as sovereign entities with primary authority and

responsibility for their members, and in keeping with this principle of tribal self-government,

view tribal governments as the appropriate non-federal parties for making decisions and carrying

out program responsibilities affecting their reservations and their members. Where tribes have

not assumed delegable programs, EPA retains responsibility for managing federal programs on

reservations. Correspondingly, as a matter of federal case law, absent an express delegation of

authority by Congress to a State, States lack civil regulatory jurisdiction over tribes. Respect for,

and protection of, this division of jurisdiction is an integral part of the federal trust responsibility.

 1

 See “Southeastern San Diego County Unclassifiable/Attainment Areas For The PM2.5 NAAQS" and

“Southeastern San Diego County Unclassifiable/Attainment Area Descriptions” in this document for further

description of these areas.
6-381

Based on EPA’s own evaluation of the nine factors for these four tribes in southeastern San

Diego County, EPA believes that a designation of unclassifiable/attainment is appropriate and is

consistent with the definition of nonattainment in §107(d)(1) of the Clean Air Act.

The justification for this designation is that these tribal areas are small in area, population and

commercial development, and are located approximately 40 miles from San Diego and are

separated from San Diego by mountain ranges, deserts and uninhabited land. Based on the

nine-factor analysis presented below, EPA has concluded that activities within these tribal lands

do not cause or contribute to PM2.5 in San Diego County, and thus are appropriately excluded

from the surrounding San Diego County PM2.5 nonattainment area and designated as individual

unclassifiable/attainment areas for the PM2.5 NAAQS. We also note that our decision to

exclude these areas from the surrounding County-wide PM2.5 nonattainment area is consistent

with the designations we recently made for these same areas for the 8-hour ozone NAAQS.

Nine-Factor Analysis:

Southeastern San Diego

Unclassifiable/Attainment Areas for the PM2.5 NAAQS

Factor 1: Emissions in areas potentially included versus excluded from the nonattainment

area

The Campo, Cuyapaipe, La Posta, Manzanita tribal areas are designated as

unclassifiable/attainment areas because their small size and eastern geographical position make

them unlikely causes or recipients of San Diego area PM2.5 exceedances.

The tribal areas are small and have very low emissions; they are also in the southeastern corner

of the county, generally downwind of areas with high observed annual PM2.5 levels. Therefore,

they are not contributors to San Diego area PM2.5 exceedances.

Nor are the proposed tribal unclassifiable/attainment areas likely recipients of PM2.5 from the

San Diego area. They are higher than the locations that experience high PM2.5, and east of

blocking mountain ranges.

Overall, PM2.5 formation is less well understood than ozone. In addition, since we are

concerned here with the annual standard, one could not just examine a few extreme episodes, but

instead must look at multiple conditions throughout the year. A fuller understanding may not be

available until an attainment plan and modeling are developed. So, for purposes of determining

the appropriate designation status for these tribal areas, this discussion will focus on the different

potentials for pollutant transport to the areas during summer and winter.

When monthly average PM2.5 exceeds 15 _g/m3, that month contributes to an annual average

over 15, and hence to exceedances of the standard. While this can occur in May or June,

concentrations exceed 15 more frequently and by a greater amount during the winter or wet

season, roughly October through March. This is consistent with the expected enhancement of
6-382

PM2.5 levels during conditions of high humidity due to the sulfate formation in the aqueous

phase.

As was described in EPA's designation for 8-hour ozone2 page 34 (2004), summer temperature

inversions, which restrict vertical dispersion and hence lead to high pollution levels, typically

occur below or about equal to the elevation of Alpine, 2000 feet. This finding is based on

meteorological modeling and analyses performed by the San Diego County Air Pollution Control

District (APCD), as well as on ozone measurements that showed ozone confined to a layer at

about this elevation. Unfortunately there is no PM2.5 data available from Alpine, but using

similar reasoning as for ozone, this elevation limitation prevents significant transport of

pollutants to the four tribal areas, which are 12 miles further inland, and range from 600 to 1300

feet higher. If a polluted layer were very thick, it could conceivably reach the lowest area,

Campo #2, by way of the canyon containing Cottonwood Hauser Creek. However, the Campo

areas are sheltered from the west by a westward spur of the Laguna Mountains, with

accompanying complex terrain. Thus for the summer months, the tribal areas are unlikely to

receive elevated PM2.5 levels.

For the winter months, when PM2.5 levels are higher, inversions occur more often at the surface

than aloft, and tend to be less intense than in summer. The inversions aloft also tend to have a

base at greater height above the ground, and so to be less constraining of pollutant dispersion.3

Surface-based inversions could hold pollutants near the ground. But in order for pollution

generated in the more urban portions of San Diego County to reach the tribal areas, they must be

transported far inland and uphill.

While winter winds are predominantly from the northwest, as in summer, they are slower. Under

some conditions, flow can even be from the northeast, down the canyons instead of up, due to the

Great Basin high pressure system that persists during winter (a strong version of this is the

"Santa Ana" winds). Thus there is less tendency for pollution to be transported inland. Upslope

flow that occurs due to surface heating could lead to pollutant transport uphill, but it is unlikely

to extend to the tribal areas. The Great Basin high just mentioned would tend to weaken the

upslope flow. In addition, in comparison to summer there is simply less heating to drive the

flow. Finally, the position of the tribal areas essentially at the mountain range crest means that

there is comparatively little slope to convert the expansion from heating into horizontal

movement of polluted air upslope. Upslope flow from the east side of the range would also tend

to retard upslope flow from the west. Therefore, during winter it is unlikely that elevated PM2.5

levels would reach these tribal areas.

One final piece of evidence to consider is the attaining air quality of Imperial County to the east.

The nearest monitor east of the tribal areas is at El Centro, where the annual design value is 9.1

_g/m3,

4

 well below the standard. While not completely conclusive due to the distance involved,

 2

 U.S. EPA., “8-hour Ozone Designation, Technical Support Document”, Chapter 3,

3

 California Air Resources Board, “Climate of the San Diego Air Basin,” December 1974.

4

 U.S. EPA, Air Quality Subsystem (AQS), 2001-2003.
6-383

this reading is consistent with the idea that the mountain range central to San Diego County is a

barrier to the movement PM2.5 from the urbanized western portion of the county, and that the

tribal areas should not be part of the nonattainment area.

Factor 2: Air Quality in potentially included versus excluded areas:

To the west, the monitor nearest these tribal areas is El Cajon located approximately 30 miles

west, which has a design value slightly above the PM2.5 NAAQS at 15.7 _g/m3.

5

 To the east,

the monitor nearest these tribal areas is El Centro located approximately 45 miles east, which has

a design value well below the PM2.5 NAAQS, at 9.1 _g/m3.

6

EPA believes the air quality in these tribal areas attains the PM2.5 NAAQS because there are

few sources in the area and it is separated from the violating monitors by both distance and

topography.

The violating monitor at El Cajon is at approximately 435 feet elevation and is separated from

these tribal areas by the Laguna Mountains. Between El Cajon and these tribal areas, the Laguna

Mountains have elevations generally in the 3000-6000 foot range. The mountains nearest to the

tribal areas are generally in the 4000-6000 foot range.

Factor 3: Population density and degree of urbanization including commercial

development in included versus excluded areas

The tribal areas are not urbanized and are sparsely populated. Nearly all of the tribal lands

discussed here have a population density of less than 50 persons per square mile. The maximum

population density on these tribal lands is less than 500 persons per square mile, and even these

areas account for only a negligible portion of the total tribal lands.

In addition to its sparse population, this area is at least 20 to 25 miles from areas with greater

than 1000 persons per square mile.7

Factor 4: Traffic and commuting patterns

These tribal areas have little population and commuting data indicates that the average

commuting time to work is 15-21 minutes. This data indicates that the average commuter from

these tribal areas does not commute daily to the San Diego area.

This area includes rural portions of Interstate 8; however, there is little traffic on these portions

of the highway compared to the San Diego area. Also, nearly all of this interstate is outside these

tribal lands and thus out of tribal jurisdiction.8

 5

 AQS 2001-2003.

6

 AQS 2001-2003.

7

 U.S. Census, 2000.
6-384

Factor 5: Expected growth (including extent, pattern and rate of growth)

These areas are separated from the urbanized portions of San Diego County by distance and

mountains. They are sparsely and lightly populated. There is no suburban or exurban growth on

these tribal lands and there is a separation of 20 to 25 miles from these tribal areas to areas with

population density of 1000 persons per square mile or greater. Because of this separation,

expansion of the San Diego area and suburbs will not impact these areas in the near future.

Because the population of these areas comprises such a small proportion of San Diego County as

a whole, growth of these areas would account for only a negligible portion of the overall growth

in San Diego County.9

Factor 6: Meteorology (weather/transport patterns)

[See discussion in Factor 1 for discussion of Meteorology (weather/transport patterns)]

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

These tribal areas are located 20 to 25 miles from the populated exurbs of San Diego. Within

those 20 to 25 miles are the Laguna Mountains. The presence of these mountains separate these

areas from the growing exurbs of the San Diego area. The elevations of the Laguna Mountains

are generally 3000 to 6000 feet, with the higher peaks immediately adjacent to these tribal lands.

These mountains form a barrier to air pollution and transport from the San Diego area to this

region. These areas are not a significant source of emissions within the county, but due to their

distance from the urbanized portions of San Diego County and the presence of the mountains

between the two, any effect on the urbanized areas of the county from emissions generated by

activities occurring on these tribal lands would be de minimis.

Factor 8: Jurisdictional boundaries (e.g., counties, air districts, Reservations, etc.)

These tribal areas are outside the jurisdiction of the State of California and San Diego County.

Factor 9: Level of control of emissions sources

EPA does not believe that there are any sources of concern in these tribal areas. With no sources

of concern, the level of control in this area is not currently relevant and does not affect PM2.5 in

San Diego.

 8

 U.S. Census, “Profile of General Demographic Characteristics: 2000" (for Campo, Cuyapaipe, and Manzanita

Reservations; profile not available for La Posta Reservation, 2000.

9

 U.S. Census, 2000.
6-385

APPENDIX A

PM2.5 Design Values for San Diego and Imperial Counties

PM2.5 Design Values 10

note: all values are annual mean with units _g/m3

San Diego County

AQS ID LOCATION ANNUAL MEAN 2001-03

06-073-1002 Escondido 15.9 _g/m3

06-073-1007 San Diego-12th St. 15.9

06-073-0003 El Cajon 15.7

06-073-0001 Chula Vista 14.6

06-073-0006 San Diego-Overland 12.8

Imperial County

AQS ID LOCATION ANNUAL MEAN 2001-03

06-025-1003 El Centro 9.1

06-025-0005 Calexico 14.4 (incomplete data)

06-025-0003 Brawley 10.6 (incomplete data)

 10

 U.S. EPA, Air Quality Subsystem (AQS), 2001-2003
6-386

APPENDIX B

Description:

Southeastern San Diego County Unclassifiable/Attainment Areas

for the PM2.5 NAAQS

List of Areas: Campo unclassifiable/attainment areas #1 and #2, Cuyapaipe

unclassifiable/attainment area, La Posta unclassifiable/attainment areas #1 and #2, and

Manzanita unclassifiable/attainment area. 11

[Note: Longitude coordinates listed are in degrees west; Latitude coordinates are in degrees

north]

CAMPO Unclassifiable/attainment AREAS #1 AND #2

CAMPO Unclassifiable/attainment AREA #1

 Degrees Degrees

 Longitude Latitude

 -116.3938522 32.6008873

 -116.3938522 32.6021004

 -116.3938370 32.6023903

 -116.3938065 32.6084938

 -116.3938217 32.6146011

 -116.3938141 32.6168747

 -116.3937836 32.6211510

 -116.3938065 32.6246223

 -116.3938141 32.6250572

 -116.3938446 32.6293945

 -116.3938599 32.6313171

 -116.3938141 32.6434937

 -116.3938370 32.6458054

 -116.3938599 32.6528740

 -116.3938599 32.6603432

 -116.3938370 32.6705208

 -116.3937683 32.6748314

 -116.3937302 32.6833992

 -116.3937073 32.6893730

 -116.3891220 32.6893845

 11

 The boundaries for these designated areas are based on coordinates of latitude and longitude derived from EPA

Region 9’s GIS database and are illustrated in a map entitled “Southeastern San Diego County

Unclassifiable/Attainment Areas for the PM-2.5 NAAQS,” included in the Technical Support Document for the

2004 PM2.5 Designations. The map and this set of coordinates are available at EPA’s Region 9 Air Division office.

The designated areas roughly approximate the boundaries of the reservations for these tribes, but their inclusion in

this table is intended for Clean Air Act planning purposes only and is not intended to be a federal determination of

the exact boundaries of the reservations. Also, the specific listing of these tribes in this table does not confer, deny,

or withdraw Federal recognition of any of the tribes so listed nor any of the tribes not listed.
6-387

 -116.3851318 32.6893387

 -116.3819046 32.6893616

 -116.3761826 32.6893501

 -116.3758469 32.6892662

 -116.3734131 32.6892815

 -116.3683548 32.6892548

 -116.3672028 32.6892776

 -116.3624268 32.6892624

 -116.3624496 32.6958275

 -116.3625107 32.7037697

 -116.3624420 32.7122650

 -116.3623810 32.7183075

 -116.3623810 32.7192383

 -116.3623886 32.7198639

 -116.3624191 32.7258682

 -116.3624344 32.7294846

 -116.3624420 32.7343102

 -116.3610229 32.7343369

 -116.3530502 32.7343521

 -116.3438492 32.7343788

 -116.3372269 32.7344055

 -116.3266830 32.7344131

 -116.3175354 32.7343712

 -116.3093948 32.7343826

 -116.3092957 32.7306824

 -116.3092194 32.7265244

 -116.3106918 32.7265053

 -116.3115997 32.7265167

 -116.3116150 32.7219543

 -116.3116837 32.7182999

 -116.3116531 32.7167130

 -116.3116837 32.7110214

 -116.3117752 32.7053833

 -116.3117752 32.7037506

 -116.3117981 32.6973648

 -116.3118744 32.6903038

 -116.3119049 32.6893005

 -116.3183517 32.6893005

 -116.3274918 32.6892776

 -116.3325958 32.6892509

 -116.3326569 32.6920052

 -116.3326645 32.6923180

 -116.3333893 32.6923409

 -116.3339844 32.6923256

 -116.3360519 32.6923256

 -116.3398743 32.6923218
6-388

 -116.3409500 32.6923447

 -116.3409805 32.6901436

 -116.3410263 32.6892700

 -116.3452530 32.6892471

 -116.3511810 32.6892128

 -116.3511658 32.6824760

 -116.3511353 32.6747093

 -116.3511200 32.6681786

 -116.3511276 32.6616478

 -116.3511276 32.6602020

 -116.3511276 32.6548462

 -116.3511581 32.6485939

 -116.3511963 32.6456985

 -116.3512039 32.6400795

 -116.3511963 32.6340599

 -116.3511734 32.6310959

 -116.3511658 32.6280823

 -116.3511658 32.6251755

 -116.3511658 32.6250687

 -116.3511353 32.6204147

 -116.3510742 32.6167946

 -116.3511276 32.6139297

 -116.3511353 32.6067390

 -116.3511581 32.6043663

 -116.3629379 32.6033897

 -116.3682709 32.6029549

 -116.3682632 32.6114883

 -116.3682709 32.6169205

 -116.3741760 32.6169586

 -116.3758469 32.6170387

 -116.3843842 32.6170082

 -116.3852768 32.6169930

 -116.3852615 32.6113052

 -116.3852692 32.6029587

 -116.3852692 32.6024170

 -116.3852921 32.6020126

 -116.3852997 32.6016350

 -116.3921661 32.6010284

 -116.3938522 32.6008873

EXCLUDING:

 Degrees Degrees

 Longitude Latitude

 -116.3432693 32.6991501

 -116.3452988 32.6991692

 -116.3474503 32.6991806
6-389

 -116.3474350 32.7004051

 -116.3474579 32.7027702

 -116.3497925 32.7027740

 -116.3511810 32.7027893

 -116.3514023 32.7027893

 -116.3517685 32.7027740

 -116.3517227 32.7033768

 -116.3517151 32.7038116

 -116.3517075 32.7044868

 -116.3516922 32.7075272

 -116.3516846 32.7100334

 -116.3511581 32.7100220

 -116.3496399 32.7100334

 -116.3474045 32.7100410

 -116.3474121 32.7089043

 -116.3474197 32.7064056

 -116.3431625 32.7063751

 -116.3431473 32.7055168

 -116.3431702 32.7037964

 -116.3431931 32.7003136

 -116.3432007 32.6993828

 -116.3432693 32.6991501

CAMPO Unclassifiable/attainment AREA #2

 Degrees Degrees

 Longitude Latitude

 -116.4757996 32.6338768

 -116.4758072 32.6354027

 -116.4758301 32.6374321

 -116.4777145 32.6373940

 -116.4801788 32.6373405

 -116.4801559 32.6390724

 -116.4801559 32.6419983

 -116.4801559 32.6445580

 -116.4801865 32.6460190

 -116.4801788 32.6482124

 -116.4778137 32.6482468

 -116.4711609 32.6484070

 -116.4685593 32.6484604

 -116.4628830 32.6485977

 -116.4628677 32.6481361

 -116.4628983 32.6449471

 -116.4628830 32.6435204

 -116.4628677 32.6412926

 -116.4610519 32.6413460

 -116.4585495 32.6413803
6-390

 -116.4585419 32.6399918

 -116.4585495 32.6376915

 -116.4623947 32.6376266

 -116.4672012 32.6376038

 -116.4671707 32.6364365

 -116.4671631 32.6339645

 -116.4698563 32.6339149

 -116.4715118 32.6338959

 -116.4757996 32.6338768

CUYAPAIPE Unclassifiable/attainment AREA

 Degrees Degrees

 Longitude Latitude

 -116.3594589 32.8148613

 -116.3758469 32.8149872

 -116.3773727 32.8149681

 -116.3773575 32.8186951

 -116.3758545 32.8187332

 -116.3730850 32.8187523

 -116.3731766 32.8223953

 -116.3758469 32.8224297

 -116.3773727 32.8223877

 -116.3945618 32.8223038

 -116.3948517 32.8368340

 -116.4123306 32.8367386

 -116.4123688 32.8439903

 -116.4124451 32.8530045

 -116.4124527 32.8585320

 -116.4125443 32.8618469

 -116.4126282 32.8657188

 -116.4084244 32.8657303

 -116.4024582 32.8657722

 -116.3950500 32.8658104

 -116.3777466 32.8657455

 -116.3774643 32.8585205

 -116.3758469 32.8586006

 -116.3601303 32.8584747

 -116.3596268 32.8445740

 -116.3596115 32.8438034

 -116.3597107 32.8406830

 -116.3598175 32.8368759

 -116.3596649 32.8295746

 -116.3594971 32.8182030

 -116.3594589 32.8148613
6-391

EXCLUDING:

 Degrees Degrees

 Longitude Latitude

 -116.3774490 32.8331528

 -116.3817902 32.8331566

 -116.3818512 32.8404427

 -116.3775253 32.8404121

 -116.3774490 32.8331528

LA POSTA Unclassifiable/attainment AREAS #1 AND #2

LA POSTA Unclassifiable/attainment AREA #1

 Degrees Degrees

 Longitude Latitude

 -116.4124756 32.7194672

 -116.4124603 32.7229614

 -116.4124603 32.7262383

 -116.4124680 32.7283859

 -116.4124603 32.7296181

 -116.4124451 32.7304344

 -116.4123917 32.7310486

 -116.4122467 32.7324371

 -116.4121933 32.7330780

 -116.4121475 32.7335663

 -116.4121094 32.7337990

 -116.4120789 32.7339172

 -116.4119797 32.7340736

 -116.4119339 32.7342529

 -116.4119034 32.7344437

 -116.4118958 32.7346458

 -116.4119186 32.7357597

 -116.4119110 32.7375832

 -116.4073563 32.7376099

 -116.4073334 32.7377701

 -116.4073029 32.7429504

 -116.4073029 32.7447739

 -116.4031143 32.7447662

 -116.4030533 32.7484016

 -116.4019165 32.7483749

 -116.4008408 32.7483826

 -116.3992996 32.7483826

 -116.3983383 32.7483864

 -116.3969803 32.7483940

 -116.3963089 32.7483864

 -116.3946991 32.7483940

 -116.3935699 32.7484093
6-392

 -116.3924103 32.7484550

 -116.3907318 32.7484818

 -116.3884659 32.7485428

 -116.3858948 32.7486076

 -116.3828659 32.7486839

 -116.3806458 32.7487526

 -116.3797913 32.7487869

 -116.3791351 32.7488022

 -116.3774567 32.7488289

 -116.3774719 32.7461090

 -116.3758469 32.7461319

 -116.3734589 32.7461510

 -116.3734436 32.7488289

 -116.3675156 32.7488518

 -116.3610306 32.7488747

 -116.3609924 32.7480240

 -116.3610306 32.7452621

 -116.3734741 32.7452507

 -116.3734512 32.7415466

 -116.3669434 32.7415543

 -116.3609619 32.7415657

 -116.3610306 32.7411308

 -116.3610229 32.7343369

 -116.3624496 32.7343407

 -116.3624344 32.7294846

 -116.3624191 32.7258682

 -116.3623886 32.7198639

 -116.3708572 32.7197227

 -116.3758316 32.7196426

 -116.3784943 32.7196579

 -116.3839035 32.7196350

 -116.3875351 32.7196198

 -116.3911743 32.7196007

 -116.3941879 32.7195473

 -116.3970032 32.7195587

 -116.3989334 32.7195625

 -116.4012909 32.7195511

 -116.4023514 32.7195320

 -116.4040070 32.7195320

 -116.4072418 32.7195053

 -116.4124756 32.7194672
6-393

LA POSTA Unclassifiable/attainment AREA #2

 Degrees Degrees

 Longitude Latitude

 -116.4203491 32.7591209

 -116.4203339 32.7655792

 -116.4203262 32.7699738

 -116.4160233 32.7700539

 -116.4160538 32.7664719

 -116.4117279 32.7666054

 -116.4117584 32.7629204

 -116.4117889 32.7593193

 -116.4203491 32.7591209

MANZANITA Unclassifiable/attainment AREA

 Degrees Degrees

 Longitude Latitude

 -116.3610229 32.7343369

 -116.3610306 32.7411308

 -116.3609619 32.7415657

 -116.3607101 32.7415619

 -116.3605652 32.7415695

 -116.3605957 32.7435303

 -116.3606262 32.7452698

 -116.3610306 32.7452621

 -116.3609924 32.7480240

 -116.3610306 32.7488747

 -116.3610229 32.7496910

 -116.3609543 32.7500534

 -116.3608856 32.7587395

 -116.3608704 32.7631874

 -116.3608627 32.7672615

 -116.3609009 32.7709351

 -116.3564072 32.7709274

 -116.3466721 32.7708702

 -116.3436737 32.7708359

 -116.3390884 32.7708054

 -116.3270569 32.7707481

 -116.3264618 32.7707291

 -116.3184509 32.7708015

 -116.3171158 32.7707672

 -116.3171768 32.7670517

 -116.3171997 32.7631454

 -116.3172760 32.7569122

 -116.3173828 32.7511406

 -116.3173828 32.7501564
6-394

 -116.3173828 32.7500610

 -116.3174362 32.7489281

 -116.3234787 32.7489281

 -116.3266678 32.7488899

 -116.3266449 32.7416649

 -116.3266830 32.7344131

 -116.3372269 32.7344055

 -116.3438492 32.7343788

 -116.3530502 32.7343521

 -116.3610229 32.7343369

EXCLUDING:

 Degrees Degrees

 Longitude Latitude

 -116.3388977 32.7581825

 -116.3431778 32.7581978

 -116.3431625 32.7613106

 -116.3431625 32.7631645

 -116.3431320 32.7654572

 -116.3387756 32.7654266

 -116.3346558 32.7654114

 -116.3346634 32.7644844

 -116.3346558 32.7631302

 -116.3346634 32.7619247

 -116.3346710 32.7581978

 -116.3388977 32.758182
6-395

APPENDIX C

Map: Southeastern San Diego County Unclassifiable/Attainment Areas

for the PM2.5 NAAQS