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AQS Count of Monitors by PQAO

REGION

STATE

CERTIFYING_AGENCY

01

09

Connecticut Department of Environmental Protection

01

09

Connecticut Department of Environmental Protection

01

09

Connecticut Department of Environmental Protection

01

23

Maine D.E.P. Bureau Of Air Quality Control, Augusta

01

23

Maine D.E.P. Bureau Of Air Quality Control, Augusta

01

23

Maine D.E.P. Bureau Of Air Quality Control, Augusta

01

25

Mass Dept Environmental Protection-Div Air Quality Control

01

25

Mass Dept Environmental Protection-Div Air Quality Control

01

25

Mass Dept Environmental Protection-Div Air Quality Control

01

33

New Hampshire Air Resources Agency

01

33

New Hampshire Air Resources Agency

01

33

New Hampshire Air Resources Agency

01

44

Rhode Island DEM And DOH

01

50

Vermont Agency Of Environmental Conservation

01

50

Vermont Agency Of Environmental Conservation

02

34

New Jersey State Department Of Environmental Protection

02

34

New Jersey State Department Of Environmental Protection

02

34

New Jersey State Department Of Environmental Protection

02

36

New York State Department Of Environmental Conservation

02

36

New York State Department Of Environmental Conservation

02

36

New York State Department Of Environmental Conservation

02

36

New York State Department Of Environmental Conservation

02

72

Puerto Rico Environmental Quality Board

02

78

Virgin Islands Department Of Planning & Natural Resources

02

78

Virgin Islands Department Of Planning & Natural Resources

02

78

Virgin Islands Department Of Planning & Natural Resources

03

10

Delaware Dept Natural Resources and Environmental Control

03

11

District Dept of Environment, Air Quality Div - DDOE/AQD

03

11

District Dept of Environment, Air Quality Div - DDOE/AQD

03

24

Maryland Department Of The Environment

03

24

Maryland Department Of The Environment

03

24

Maryland Department Of The Environment

03

42

Allegany County Health Department

03

42

Allegany County Health Department

03

42

Allegany County Health Department

03

42

Pennsylvania Department Of Environmental Protection

03

42

Pennsylvania Department Of Environmental Protection

03

42

Pennsylvania Department Of Environmental Protection

03

42

Philadelphia Air Management Services

03

51

Virginia Department of Environmental Quality

03

51

Virginia Department of Environmental Quality

03

51

Virginia Department of Environmental Quality

03

54

West Virginia Air Pollution Control Commission

03

54

West Virginia Air Pollution Control Commission

03

54

West Virginia Air Pollution Control Commission

03

54

West Virginia Air Pollution Control Commission

03

54

West Virginia Air Pollution Control Commission

04

01

Al Dept Of Env Mgt

04

01

Al Dept Of Env Mgt

04

01

Al Dept Of Env Mgt

04

01

City of Huntsville, Div of Natural Resources

REGION STATE CERTIFYING_AGENCY

04

01

Jefferson County, AL Department Of Health

04

01

Jefferson County, AL Department Of Health

04

01

Jefferson County, AL Department Of Health

04

01

Jefferson County, AL Department Of Health

04

12

Florida Department of Environmental Protection (FDEP)

04

12

Florida Department of Environmental Protection (FDEP)

04

12

Florida Department of Environmental Protection (FDEP)

04

12

Florida Department of Environmental Protection (FDEP)

04

13

Georgia Air Protection Branch Ambient Monitoring Program

04

13

Georgia Air Protection Branch Ambient Monitoring Program

04

13

Georgia Air Protection Branch Ambient Monitoring Program

04

21

Kentucky Division For Air Quality

04

21

Kentucky Division For Air Quality

04

21

Kentucky Division For Air Quality

04

28

Mississippi DEQ, Office Of Pollution

04

28

Mississippi DEQ, Office Of Pollution

04

37

North Carolina Dept Of Environment And Natural Resources

04

37

North Carolina Dept Of Environment And Natural Resources

04

37

North Carolina Dept Of Environment And Natural Resources

04

37

North Carolina Dept Of Environment And Natural Resources

04

45

South Carolina Department Health And Environmental Control

04

45

South Carolina Department Health And Environmental Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

04

47

Tennessee Division Of Air Pollution Control

05

17

Illinois Environmental Protection Agency

05

17

Illinois Environmental Protection Agency

05

17

Illinois Environmental Protection Agency

05

17

Illinois Environmental Protection Agency

05

17

Illinois Environmental Protection Agency

05

17

Illinois Environmental Protection Agency

05

17

Indiana Depart Of Environ Management/Office Of Air Quality

05

17

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

18

Indiana Depart Of Environ Management/Office Of Air Quality

05

26

Michigan Dept Of Environmental Quality-Air Quality Division

05

26

Michigan Dept Of Environmental Quality-Air Quality Division

05

26

Michigan Dept Of Environmental Quality-Air Quality Division

REGION STATE CERTIFYING_AGENCY

05

26

Michigan Dept Of Environmental Quality-Air Quality Division

05

26

Michigan Dept Of Environmental Quality-Air Quality Division

05

27

Minnesota Pollution Control Agency, Division Of Air Quality

05

27

Minnesota Pollution Control Agency, Division Of Air Quality

05

27

Minnesota Pollution Control Agency, Division Of Air Quality

05

39

Hamilton County Department Of Environmental Services

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

39

Ohio EPA Central Office

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

05

55

Wisconsin Dept Of Natural Resources, Air Monitoring Section

06

05

Arkansas Department Of Environmental Quality

06

05

National Park Service

06

05

USEPA - Clean Air Markets Division

06

22

National Park Service

06

22

State Of Louisiana

06

35

Albuquerque Environmental Health Department, Air Quality Division

06

35

Eastern Research Group

06

35

National Park Service

06

35

Navajo Nation, AZ, NM, UT

06

35

New Mexico Environment Department

06

35

Pueblo of Jemez, NM

06

40

Arkansas Department Of Environmental Quality

06

40

Cherokee Nation, Oklahoma

06

40

Choctaw Nation of Oklahoma

06

40

Delaware Nation, OK

06

40

Eastern Research Group

06

40

Kaw Nation

06

40

National Park Service

REGION STATE CERTIFYING_AGENCY

06

40

Oklahoma Dept. Of Environmental Quality Air Quality Division

06

40

Quapaw Tribe of Indians, OK

06

48

City of El Paso-Air Quality Program

06

48

National Park Service

06

48

South East Texas Regional Planning Commission (SETRPC)

06

48

Texas Commission On Environmental Quality

06

48

USEPA - Clean Air Markets Division

07

19

Iowa Department Of Natural Resources

07

19

Iowa Department Of Natural Resources

07

19

Iowa Department Of Natural Resources

07

19

Iowa Department Of Natural Resources

07

19

University Hygenic Laboratory

07

20

Kansas Department Of Health And Environment

07

20

Kansas Department Of Health And Environment

07

20

Kansas Department Of Health And Environment

07

29

Missouri Dept Of Natural Resources

07

29

Missouri Dept Of Natural Resources

07

29

Missouri Dept Of Natural Resources

07

29

Missouri Dept Of Natural Resources

07

29

Missouri Dept Of Natural Resources

07

29

Missouri Dept Of Natural Resources

07

29

Missouri Dept Of Natural Resources

07

31

Nebraska Department Of Environmental Control

07

31

Nebraska Department Of Environmental Control

07

31

Nebraska Department Of Environmental Control

07

31

Nebraska Department Of Environmental Control

07

31

Nebraska Department Of Environmental Control

08

08

Colorado Department of Public Health And Environment

08

08

Southern Ute Indian Tribe of Southern Ute Reservation, CO

08

30

Confederated Salish & Kootenai Tribes of Flathead Reservation, MT

08

30

Mt Dept Of Environmental Quality, Air Quality Division

08

30

Northern Cheyenne Tribe of Northern Cheyenne Indian Reservation, MT

08

38

North Dakota State Department Of Health

08

46

South Dakota Dept Environmental Protection Air Quality Prog

08

49

Utah Department Of Environmental Quality

08

56

Wyoming Air Quality Division, Dept Of Environmental Quality

09

04

Ak Chin Indian Community of Maricopa (Ak Chin) Indian Reservation, AZ

09

04

Arizona Department Of Environmental Quality

09

04

Fort McDowell Yavapai Nation, AZ

09

04

Freeport McMoRan Miami, Inc.

09

04

Gila River Indian Community of Gila River Indian Reservation, AZ

09

04

Hualapai Indian Tribe of Hualapai Indian Reservation, AZ

09

04

Maricopa County Air Quality

09

04

National Park Service

09

04

Navajo Nation, AZ, NM, UT

09

04

Pima County Health Department

09

04

Pinal County APCD

09

04

Salt River Pima-Maricopa Indian Community of Salt River Reservation, AZ

09

04

White Mountain Apache Tribe of Ft Apache Reservation, AZ

09

06

Antelope Valley APCD

09

06

Bay Area Air Quality Management District

09

06

Bay Area Air Quality Management District

REGION STATE CERTIFYING_AGENCY

09

06

Cabazon Band of Mission Indians, CA

09

06

California Air Resources Board

09

06

Campo Band of Diegueno Mission Indians of Campo Indian Reservation, CA

09

06

Cortina Indian Rancheria of Wintun Indians, CA

09

06

Fort Independence Indian Community of Paiute Indians of Ft Independence, CA

09

06

Great Basin Unified APCD

09

06

Hoopa Valley Tribe, CA

09

06

La Posta Band of Dieguento Mission Indians of La Posta Indian Reservation, CA

09

06

Manzanita Band of Diegueno Mission Indians of Manzanita Reservation, CA

09

06

Mojave Desert AQMD

09

06

Monterey Bay Unified APCD

09

06

Morongo Band of Mission Indians, CA

09

06

National Park Service

09

06

Paiute-Shoshone Indians of Bishop Community of Bishop Colony, CA

09

06

Paiute-Shoshone Indians of the Lone Pine Community of Lone Pine Reservation,CA

09

06

Pala Band of Luiseno Mission Indians of Pala Reservation, CA

09

06

Pechanga Band of Luiseno Mission Indians of Pechanga Reservation, CA

09

06

Picayune Ranceria of Chukchansi Indians of California

09

06

Placer County APCD

09

06

Sacramento County APCD

09

06

San Diego County Air Pollution Control District

09

06

San Joaquin Valley Unified Air Pollution Control District

09

06

San Joaquin Valley Unified Air Pollution Control District

09

06

San Luis Obispo County APCD

09

06

Santa Barbara County APCD

09

06

Santa Rosa Indian Community of Santa Rosa Rancheria, CA

09

06

Shasta County APCD

09

06

South Coast Air Quality Management District

09

06

Torres-Martinez Cahuilla Indians, California

09

06

Ventura County APCD

09

06

Ventura County APCD

09

15

Hawaii State Department Of Health

09

15

Hawaii State Department Of Health

09

32

Clark County, NV DAQEM

09

32

Clark County, NV DAQEM

09

32

Nevada Division Of Environmental Protection

09

32

Nevada Division Of Environmental Protection

09

32

Nevada Division Of Environmental Protection

09

32

Washoe County District Health Department

09

32

Washoe County District Health Department

10

02

Alaska Department Of Environmental Conservation

10

02

Alaska Department Of Environmental Conservation

10

16

Idaho Air Quality Bureau

10

16

Idaho Air Quality Bureau

10

16

Shoshone-Bannock Tribes of Fort Hall Reservation of Idaho

10

41

Oregon Department Of Environmental Quality

10

41

Oregon Department Of Environmental Quality

10

53

Swinomish Indians of Swinomish Reservation, WA

10

53

Washington State Department Of Ecology

10

53

Washington State Department Of Ecology

25

80

Arizona Department Of Environmental Quality

25

80

California Air Resources Board

25 80 City of El Paso-Air Quality Program

25 80 Semarnap

25 80 Tracer Technologies

PQAO

MONITORS

Connecticut Department of Environmental Protection 51

National Park Service 1

USEPA - Clean Air Markets Division 1

Maine D.E.P. Bureau Of Air Quality Control, Augusta 48

National Park Service 6

USEPA - Clean Air Markets Division 2

AECOM 2

Mass Dept Environmental Protection-Div Air Quality Control 77

National Park Service 3

National Park Service 1

New Hampshire Air Resources Agency 49

USEPA - Clean Air Markets Division 1

Rhode Island DEM And DOH 25

National Park Service 3

Vermont Agency Of Environmental Conservation 17

National Park Service 1

New Jersey State Department Of Environmental Protection 75

USEPA - Clean Air Markets Division 1

National Park Service 3

New York State Department Of Environmental Conservation 125

St. Regis Mohawk Tribe, New York 4

USEPA - Clean Air Markets Division 2

Puerto Rico Environmental Quality Board 38

Hovensa L. L. C. 5

National Park Service 1

Virgin Islands Department Of Planning & Natural Resources 7

Delaware Dept Natural Resources and Environmental Control 28

District Dept of Environment, Air Quality Div - DDOE/AQD 22

National Park Service 1

National Park Service 3

State Of Maryland Air Management Administration 61

USEPA - Clean Air Markets Division 2

Allegheny County,PA Health Department 44

National Park Service 1

Pennsylvania Department Of Environmental Protection 5

National Park Service 2

Pennsylvania Department Of Environmental Protection 192

USEPA - Clean Air Markets Division 5

Philadelphia Air Management Services 29

National Park Service 3

USEPA - Clean Air Markets Division 2

Virginia Department of Environmental Quality 101

Ashland Oil 4

National Park Service 1

Shell Engineering & Assoc., MO 1

USEPA - Clean Air Markets Division 2

West Virginia Air Pollution Control Commission 67

Al Dept Of Env Mgt 34

National Park Service 1

USEPA - Clean Air Markets Division 1

Al Dept Of Env Mgt 7

Al Dept Of Env Mgt 35

Eastern Research Group 4

Jefferson County, AL Department Of Health 2

National Park Service 1

Florida Department of Environmental Protection (FDEP) 186

Hillsborough County Environmental Protection Commission 1

National Park Service 5

USEPA - Clean Air Markets Division 2

Georgia Air Protection Branch Ambient Monitoring Program 78

National Park Service 3

USEPA - Clean Air Markets Division 1

Kentucky Division For Air Quality 89

National Park Service 7

USEPA - Clean Air Markets Division 4

Mississippi DEQ, Office Of Pollution 32

USEPA - Clean Air Markets Division 1

Eastern Band Of Cherokee Indians of North Carolina 4

National Park Service 4

North Carolina Dept Of Environment And Natural Resources 132

USEPA - Clean Air Markets Division 4

National Park Service 2

South Carolina Department Health And Environmental Control 82

Bowater Southern Paper Company 3

Chattanooga-Hamilton County Air Pollution Control 2

Exide Corporation 4

Horsehead Corp 3

Knox County Department Of Air Pollution Control 6

National Park Service 5

Savage Zinc Incinc Company 2

Tennessee Division Of Air Pollution Control 85

Tennessee Luttrell Lime 2

Tennessee Valley Authority 23

USEPA - Clean Air Markets Division 2

Cook County Department of Environmental Control 25

Illinois Environmental Protection Agency 82

National Park Service 2

PSGC (Prairie State Generating Company, LLC), IL 1

USEPA - Clean Air Markets Division 5

Washington University in St. Louis 3

Duke Energy 1

Indiana Depart Of Environ Management/Office Of Air Quality 1

Duke Energy 4

Hoosier Energy 1

Indiana Depart Of Environ Management/Office Of Air Quality 148

Indianapolis Power And Light Company 2

National Park Service 1

Northern Indiana Public Service Company 3

Richmond Power And Light 1

USEPA - Clean Air Markets Division 2

Inter-tribal Council of MIchigan, Inc. 2

Marathon Oil 12

Michigan Dept Of Environmental Quality-Air Quality Division 98

National Park Service 4

USEPA - Clean Air Markets Division 3

Minnesota Chippewa Tribe, MN (Leech Lake Band) 2

Minnesota Pollution Control Agency, Division Of Air Quality 95

National Park Service 6

Hamilton County Department Of Environmental Services 4

Akron Regional Air Pollution Control Agency 13

Canton City Health Department Air Pollution Control 7

City of Toledo, Environmental Services Division 10

Cleveland Air Pollution Control Agency 34

Dayton Regional Air Pollution Control Agency 21

Hamilton County Department Of Environmental Services 38

Lake County Health Department Division Air Pollution Control 9

Mahoning-Trumbull Air Pollution Control Agency 17

National Park Service 1

Ohio EPA, Central District Office 18

Ohio EPA, Northeast District Office 13

Ohio EPA, Northwest District Office 8

Ohio EPA, Southeast District Office 17

Ohio EPA, Southwest District Office 2

Portsmouth City Health Dept Division Air Pollution Control 12

Shell Engineering & Assoc., MO 2

URSCorp, TX 5

USEPA - Clean Air Markets Division 3

Chippewa Sand Company, LLC 1

Great Northern Sands, LLC 1

RTP Environmental Associates 1

Smart Sand, LLC 1

Superior Silica Sands, LLC 1

Taylor Frac, LLC 1

U.S. Silica Company 1

USEPA - Clean Air Markets Division 1

Wisconsin Department of Administration(DOA) 1

Wisconsin Dept Of Natural Resources, Air Monitoring Section 88

Arkansas Department Of Environmental Quality 38

National Park Service 2

USEPA - Clean Air Markets Division 1

National Park Service 2

State Of Louisiana 82

Albuquerque Environmental Health Department, Air Quality Division 24

Eastern Research Group 3

National Park Service 8

Navajo Nation, AZ, NM, UT 5

New Mexico Environment Department 54

Pueblo of Jemez, NM 2

Arkansas Department Of Environmental Quality 2

Cherokee Nation, Oklahoma 16

Choctaw Nation of Oklahoma 1

Delaware Nation, OK 1

Eastern Research Group 8

Kaw Nation 1

National Park Service 3

Oklahoma Dept. Of Environmental Quality Air Quality Division 52

Quapaw Tribe of Indians, OK 5

City of El Paso-Air Quality Program 1

National Park Service 4

South East Texas Regional Planning Commission (SETRPC) 4

Texas Commission On Environmental Quality 245

USEPA - Clean Air Markets Division 2

Linn County Health Department 10

National Park Service 1

Polk County Physical Planning 12

University Hygenic Laboratory 61

University Hygenic Laboratory 1

Kansas Department Of Health And Environment 52

National Park Service 4

USEPA - Clean Air Markets Division 1

Doe Run Buick 4

Doe Run Glover 3

Doe Run Herculaneum 9

Eastern Research Group 2

Missouri Laboratory Services Program 80

National Park Service 4

Springfield City Utilities, MO 2

Lincoln-Lancaster County Health Department 2

National Park Service 4

Nebraska Department Of Environmental Control 12

Omaha-Douglas County Health Department 20

USEPA - Clean Air Markets Division 1

Colorado Department of Public Health And Environment 87

Southern Ute Indian Tribe of Southern Ute Reservation, CO 8

Confederated Salish & Kootenai Tribes of Flathead Reservation, MT 3

Mt Dept Of Environmental Quality, Air Quality Division 48

Northern Cheyenne Tribe of Northern Cheyenne Indian Reservation, MT 7

North Dakota State Department Of Health 46

South Dakota Dept Environmental Protection Air Quality Prog 44

Utah Department Of Environmental Quality 73

Wyoming Air Quality Division, Dept Of Environmental Quality 91

Ak Chin Indian Community of Maricopa (Ak Chin) Indian Reservation, AZ 2

Arizona Department Of Environmental Quality 43

Fort McDowell Yavapai Nation, AZ 2

Freeport McMoRan Miami, Inc. 3

Gila River Indian Community of Gila River Indian Reservation, AZ 4

Hualapai Indian Tribe of Hualapai Indian Reservation, AZ 4

Maricopa County Air Quality 66

National Park Service 21

Navajo Nation, AZ, NM, UT 4

Pima County Health Department 29

Pinal County APCD 22

Salt River Pima-Maricopa Indian Community of Salt River Reservation, AZ 10

White Mountain Apache Tribe of Ft Apache Reservation, AZ 2

California Air Resources Board 6

Bay Area Air Quality Management District 91

California Air Resources Board 4

Cabazon Band of Mission Indians, CA 1

California Air Resources Board 229

Campo Band of Diegueno Mission Indians of Campo Indian Reservation, CA 3

Cortina Indian Rancheria of Wintun Indians, CA 1

Fort Independence Indian Community of Paiute Indians of Ft Independence, CA 1

California Air Resources Board 20

Hoopa Valley Tribe, CA 1

La Posta Band of Dieguento Mission Indians of La Posta Indian Reservation, CA 4

Manzanita Band of Diegueno Mission Indians of Manzanita Reservation, CA 1

California Air Resources Board 21

California Air Resources Board 15

Morongo Band of Mission Indians, CA 2

National Park Service 35

Paiute-Shoshone Indians of Bishop Community of Bishop Colony, CA 1

Paiute-Shoshone Indians of the Lone Pine Community of Lone Pine Reservation,CA 1

Pala Band of Luiseno Mission Indians of Pala Reservation, CA 6

Pechanga Band of Luiseno Mission Indians of Pechanga Reservation, CA 5

Picayune Ranceria of Chukchansi Indians of California 3

California Air Resources Board 2

California Air Resources Board 2

San Diego County Air Pollution Control District 54

California Air Resources Board 44

San Joaquin Valley Unified Air Pollution Control District 4

California Air Resources Board 17

California Air Resources Board 38

Santa Rosa Indian Community of Santa Rosa Rancheria, CA 1

California Air Resources Board 3

South Coast Air Quality Management District 202

Torres-Martinez Cahuilla Indians, California 2

California Air Resources Board 25

Ventura County APCD 1

Hawaii State Department Of Health 36

National Park Service 4

Clark County, NV DAQEM 40

Las Vegas Tribe of Paiute Indians of the Las Vegas Indian Colony, NV 2

National Park Service 5

Nevada Division Of Environmental Protection 8

Walker River Paiute Tribe of Walker River Reservation, NV 1

Pyramid Lake Paiute Tribe of Pyramid Lake Reservation, NV 2

Washoe County District Health Department 27

Alaska Department Of Environmental Conservation 45

National Park Service 7

Idaho Department Of Health And Welfare-Environment Division 30

National Park Service 4

Shoshone-Bannock Tribes of Fort Hall Reservation of Idaho 4

National Park Service 6

Oregon Department Of Environmental Quality 44

Swinomish Indians of Swinomish Reservation, WA 3

National Park Service 13

Washington State Department Of Ecology 45

Arizona Department Of Environmental Quality 3

California Air Resources Board 14

City of El Paso-Air Quality Program 11

Semarnap 39

Tracer Technologies 11