SIP Status Reports

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Status of California Designated Areas

California Areas by NAAQS
NOTE: As of 03/12/2021, these reports are no longer being updated. For the latest information, see the SIP Status Tools.

Jump to California section for: CO (1971) Lead (1978) Lead (2008) NO2 (1971) Ozone-1Hr (1979) Ozone-8Hr (1997) Ozone-8Hr (2008) Ozone-8Hr (2015) PM-10 (1987) PM-2.5 (1997) PM-2.5 (2006) PM-2.5 (2012) SO2 (1971) SO2 (2010)


California CO (1971) Areas    Return to map
 
Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(ppm)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Bakersfield Area Maintenance 11/15/1990 Not Classified 468,092 2019 1.1 Yes 1 / 0  
 
07/03/1996 06/01/1998
63 FR 15305
Chico Area Maintenance 11/15/1990 Moderate <= 12.7ppm 86,963 2019 6.4 Yes 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305
Fresno Area Maintenance 11/15/1990 Moderate > 12.7ppm 631,483 2019 1.8 Yes 6 / 5  
 
07/03/1996 06/01/1998
63 FR 15305
Lake Tahoe North Shore Area Maintenance 11/15/1990 Not Classified 16,132 2019   No Data 0 / 0  
 
07/03/1996 06/01/1998
63 FR 15305
Lake Tahoe South Shore Area Maintenance 11/15/1990 Moderate <= 12.7ppm 43,110 2019   No Data 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305
Los Angeles-South Coast Air Basin Area Maintenance 11/15/1990 Serious 15,799,134 2019 3.1 Yes 7 / 7  
 
02/24/2006 06/11/2007
72 FR 26718
Modesto Area Maintenance 11/15/1990 Moderate <= 12.7ppm 320,707 2019 1.9 Yes 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305
Sacramento Area Maintenance 11/15/1990 Moderate <= 12.7ppm 1,530,116 2019 3.6 Yes 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305
San Diego Area Maintenance 11/15/1990 Moderate <= 12.7ppm 2,909,194 2019 1.7 Yes 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305
San Francisco-Oakland-San Jose Area Maintenance 11/15/1990 Moderate <= 12.7ppm 4,296,499 2019 3.0 Yes 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305
Stockton Area Maintenance 11/15/1990 Moderate <= 12.7ppm 373,545 2019 2.4 Yes 4 / 3  
 
07/03/1996 06/01/1998
63 FR 15305

California Lead (1978) Areas     Return to map Top of page

No designated areas for this pollutant.

California Lead (2008) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(µg/m3)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Los Angeles County-South Coast Air Basin Nonattainment 12/31/2010   9,436,927 2017-2019 0.01 Yes 6 / 6  
 
   

California NO2 (1971) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(ppb)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Los Angeles-South Coast Air Basin Area Maintenance 11/15/1990   15,799,134 2019 29 Yes 0 / 0  
 
02/05/1997 09/22/1998
63 FR 39747

California Ozone-1Hr (1979) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(ppm)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Chico Area Nonattainment (NAAQS revoked) 11/15/1990 Transitional 220,000 2017-2019 0.091 Yes 2 / 0  
 
08/18/1997  
East Kern County Area Maintenance (NAAQS revoked) 12/10/2001 Serious 141,398 2017-2019 0.102 Yes 27 / 26  
 
  06/21/2004
69 FR 21731
Imperial County Area Nonattainment (NAAQS revoked) 11/15/1990 Transitional 174,528 2017-2019 0.105 Yes 2 / 0  
 
   
Los Angeles-South Coast Air Basin Area Nonattainment (NAAQS revoked) 11/15/1990 Extreme 15,798,191 2017-2019 0.144 No 42 / 38  
 
   
Monterey Bay Area Maintenance (NAAQS revoked) 11/15/1990 Moderate 732,708 2017-2019 0.084 Yes 20 / 11 02/16/2010
74 FR 66916
07/14/1994 03/18/1997
62 FR 2597
Morongo Band of Mission Indians Nonattainment (NAAQS revoked) 11/15/1990 Severe-17 913 2017-2019 0.127 No 0 / 0  
 
   
Sacramento Metro Area Nonattainment (NAAQS revoked) 11/15/1990 Severe-15 2,336,542 2017-2019 0.113 Yes 71 / 47 11/19/2012
77 FR 64036
   
San Diego Area Maintenance (NAAQS revoked) 11/15/1990 Serious 3,095,313 2017-2019 0.105 Yes 33 / 33  
 
12/20/2002 07/28/2003
68 FR 37976
San Francisco-Bay Area Nonattainment (NAAQS revoked) 07/10/1998 Other 6,896,958 2017-2019 0.103 Yes 26 / 24 05/24/2004
69 FR 21717
11/12/1993  
San Joaquin Valley Area Nonattainment (NAAQS revoked) 11/15/1990 Extreme 3,830,257 2017-2019 0.116 Yes 36 / 30 08/17/2016
81 FR 46608
   
Santa Barbara-Santa Maria-Lompoc Area Maintenance (NAAQS revoked) 11/15/1990 Serious 423,895 2017-2019 0.082 Yes 22 / 22  
 
02/21/2003 08/08/2003
68 FR 40789
Southeast Desert Modified AQMA Area Nonattainment (NAAQS revoked) 11/15/1990 Severe-17 1,194,366 2017-2019 0.126 No 42 / 27 05/15/2015
80 FR 20166
   
Ventura County Area Nonattainment (NAAQS revoked) 11/15/1990 Severe-15 823,318 2017-2019 0.099 Yes 29 / 23 07/27/2009
74 FR 25153
   
Yuba City Area Nonattainment (NAAQS revoked) 11/15/1990 Transitional 136,872 2017-2019 0.095 Yes 2 / 0  
 
02/26/1997  

California Ozone-8Hr (1997) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(ppm)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Amador and Calaveras Cos. (Central Mountain Cos.) Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Moderate 83,669 2017-2019 0.073 Yes 52 / 0 01/02/2013
77 FR 71551
   
Chico Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Marginal 220,000 2017-2019 0.062 Yes 3 / 1 01/02/2013
77 FR 71551
   
Imperial County Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Moderate 174,528 2017-2019 0.079 Yes 53 / 49 12/22/2014
79 FR 63332
   
Kern County (Eastern Kern) Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Moderate 95,314 2017-2019 0.081 Yes 52 / 0 01/02/2013
77 FR 71551
   
Los Angeles and San Bernardino Counties (Western Mojave Desert) Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Severe 15 868,350 2017-2019 0.095 No 108 / 63  
 
   
Los Angeles-South Coast Air Basin Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Extreme 15,715,184 2017-2019 0.108 No 61 / 47  
 
   
Mariposa and Tuolumne Cos. (Southern Mountain Counties) Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Moderate 73,616 2017-2019 0.077 Yes 52 / 0 01/02/2013
77 FR 71551
   
Morongo Band of Mission Indians Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Severe 17 913 2017-2019 0.101 No 57 / 0  
 
   
Nevada County (Western part) Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Moderate 82,393 2017-2019 0.085 No 52 / 46 01/02/2013
77 FR 71551
   
Pechanga Band of Luiseņo Mission Indians of the Pechanga Reservation Maintenance (NAAQS revoked) 06/15/2004 Subpart 2/Severe 17 2,844 2017-2019 0.079 Yes 57 / 0  
 
  04/03/2015
80 FR 18120
Riverside County (Coachella Valley) Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Extreme 425,425 2017-2019 0.089 No 63 / 44  
 
   
Sacramento Metro Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Severe 15 2,243,911 2017-2019 0.086 No 256 / 215  
 
   
San Diego Maintenance (NAAQS revoked) 06/15/2004 Subpart 2/Moderate 3,093,345 2017-2019 0.082 Yes 53 / 1  
 
12/28/2012 07/05/2013
78 FR 33230
San Francisco Bay Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Marginal 6,970,997 2017-2019 0.073 Yes 3 / 1 01/07/2021
85 FR 64046
   
San Joaquin Valley Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Extreme 3,842,586 2017-2019 0.088 No 61 / 59  
 
   
Sutter County (part) (Sutter Buttes) Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Marginal 33 2017-2019   Insufficient Data 3 / 0 01/02/2013
77 FR 71551
   
Ventura County (part) Area Nonattainment (NAAQS revoked) 06/15/2004 Subpart 2/Serious 823,360 2017-2019 0.076 Yes 59 / 39 01/02/2013
77 FR 71551
   

California Ozone-8Hr (2008) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(ppm)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Calaveras County Nonattainment 07/20/2012 Marginal 45,578 2017-2019 0.073 Yes 3 / 3 06/03/2016
81 FR 26697
   
Chico (Butte County) Nonattainment 07/20/2012 Marginal 220,000 2017-2019 0.062 Yes 3 / 3 06/03/2016
81 FR 26697
   
Imperial County Nonattainment 07/20/2012 Moderate 174,528 2017-2019 0.079 No 54 / 53 03/30/2020
85 FR 11817
   
Kern County (Eastern Kern) Nonattainment 07/20/2012 Serious 95,176 2017-2019 0.081 No 57 / 0  
 
   
Los Angeles-San Bernardino Counties (West Mojave Desert) Nonattainment 07/20/2012 Severe 15 868,380 2017-2019 0.095 No 107 / 92  
 
   
Los Angeles-South Coast Air Basin Nonattainment 07/20/2012 Extreme 15,719,485 2017-2019 0.108 No 59 / 56  
 
   
Mariposa County Nonattainment 07/20/2012 Moderate 18,251 2017-2019 0.077 No 54 / 3 09/23/2019
84 FR 44238
   
Morongo Band of Mission Indians Nonattainment 07/20/2012 Serious 913 2017-2019 0.101 No 53 / 0  
 
   
Nevada County (Western part) Nonattainment 07/20/2012 Serious 82,107 2017-2019 0.085 No 57 / 51  
 
   
Pechanga Band of Luiseņo Mission Indians of the Pechanga Reservation Nonattainment 07/20/2012 Moderate 2,844 2017-2019 0.079 No 53 / 0  
 
   
Riverside County (Coachella Valley) Nonattainment 07/20/2012 Severe 15 425,806 2017-2019 0.089 No 58 / 54  
 
   
Sacramento Metro Nonattainment 07/20/2012 Severe 15 2,241,057 2017-2019 0.086 No 254 / 177  
 
   
San Diego County Nonattainment 07/20/2012 Serious 3,095,199 2017-2019 0.082 No 59 / 3  
 
   
San Francisco Bay Area Nonattainment 07/20/2012 Marginal 6,973,020 2017-2019 0.073 Yes 3 / 2 06/03/2016
81 FR 26697
   
San Joaquin Valley Nonattainment 07/20/2012 Extreme 3,842,365 2017-2019 0.088 No 59 / 57  
 
   
San Luis Obispo (Eastern San Luis Obispo) Nonattainment 07/20/2012 Marginal 1,649 2017-2019 0.070 Yes 3 / 2 01/20/2017
81 FR 93620
   
Tuscan Buttes Nonattainment 07/20/2012 Marginal 0 2017-2019   Insufficient Data 3 / 0 06/03/2016
81 FR 26697
   
Ventura County Nonattainment 07/20/2012 Serious 823,262 2017-2019 0.076 No 54 / 53  
 
   

California Ozone-8Hr (2015) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(ppm)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Amador County Nonattainment 08/03/2018 Marginal 38,091 2017-2019 0.071 No 3 / 0  
 
   
Butte County Nonattainment 08/03/2018 Marginal 220,000 2017-2019 0.074 No 3 / 0  
 
   
Calaveras County Nonattainment 08/03/2018 Marginal 45,578 2017-2019 0.073 No 3 / 2  
 
   
Imperial County Nonattainment 08/03/2018 Marginal 174,528 2017-2019 0.079 No 3 / 0  
 
   
Kern County (Eastern Kern) Nonattainment 08/03/2018 Moderate 95,066 2017-2019 0.081 No 52 / 0  
 
   
Los Angeles-San Bernardino Counties (West Mojave Desert) Nonattainment 08/03/2018 Severe-15 866,960 2017-2019 0.095 No 105 / 0  
 
   
Los Angeles-South Coast Air Basin Nonattainment 08/03/2018 Extreme 15,702,771 2017-2019 0.108 No 58 / 0  
 
   
Mariposa County Nonattainment 08/03/2018 Marginal 18,251 2017-2019 0.077 No 3 / 2  
 
   
Morongo Band of Mission Indians Nonattainment 08/03/2018 Serious 932 2017-2019 0.101 No 53 / 0  
 
   
Nevada County (Western part) Nonattainment 08/03/2018 Moderate 82,042 2017-2019 0.085 No 52 / 1  
 
   
Pechanga Band of Luiseņo Mission Indians of the Pechanga Reservation Nonattainment 08/03/2018 Marginal 652 2017-2019 0.079 No 3 / 0  
 
   
Riverside County (Coachella Valley) Nonattainment 08/03/2018 Severe-15 425,029 2017-2019 0.089 No 57 / 0  
 
   
Sacramento Metro Nonattainment 08/03/2018 Moderate 2,240,448 2017-2019 0.086 No 241 / 0  
 
   
San Diego County Nonattainment 08/03/2018 Moderate 3,077,287 2017-2019 0.082 No 53 / 1  
 
   
San Francisco Bay Area Nonattainment 08/03/2018 Marginal 6,969,365 2017-2019 0.073 No 3 / 0  
 
   
San Joaquin Valley Nonattainment 08/03/2018 Extreme 3,841,897 2017-2019 0.088 No 58 / 0  
 
   
San Luis Obispo (Eastern part) Nonattainment 08/03/2018 Marginal 1,290 2017-2019 0.070 Yes 3 / 0  
 
   
Sutter Buttes Nonattainment 08/03/2018 Marginal 3 2017-2019   Insufficient Data 3 / 0  
 
   
Tuolumne County Nonattainment 08/03/2018 Marginal 55,365 2017-2019 0.076 No 3 / 0  
 
   
Tuscan Buttes Nonattainment 08/03/2018 Marginal (Rural Transport) 0 2017-2019 0.074 No 3 / 0  
 
   
Ventura County Nonattainment 08/03/2018 Serious 820,808 2017-2019 0.076 No 54 / 0  
 
   

California PM-10 (1987) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Average
Estimated
Exceedances
(est. exc.)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Coso Junction Maintenance 11/15/1990 Moderate 7,333 2017-2019 1.7 No 3 / 0 06/18/2010
75 FR 27944
07/14/2010 10/04/2010
75 FR 54031
East Kern County Area Nonattainment 11/15/1990 Serious 125,950 2017-2019 0.3 Yes 4 / 3  
 
   
Imperial County; Imperial Valley planning area Maintenance 11/15/1990 Serious 146,905 2017-2019 1.0 Yes 4 / 4  
 
02/13/2019 10/19/2020
85 FR 58286
Indian Wells Maintenance 11/15/1990 Moderate 15,449 2017-2019 0.3 Yes 3 / 2  
 
  06/06/2003
68 FR 24368
Inyo County; Owens Valley planning area Nonattainment 11/15/1990 Serious 7,333 2017-2019 4.7 No 4 / 3  
 
   
Mono County; Mammoth Lake planning area Maintenance 11/15/1990 Moderate 7,133 2017-2019 2.2 No 3 / 2  
 
09/11/1991 11/04/2015
80 FR 60049
Mono County; Mono Basin Nonattainment 12/29/1993 Moderate 285 2017-2019 13.4 No 3 / 0  
 
   
Riverside County; Coachella Valley planning area Nonattainment 11/15/1990 Serious 257,794 2017-2019 4.5 No 3 / 2  
 
03/29/2010  
Riverside, Los Angeles, Orange, and San Bernardino Counties; South Coast Air Basin Maintenance 11/15/1990 Serious 15,799,134 2017-2019 2.0 No 3 / 3  
 
04/28/2010 07/26/2013
78 FR 38223
Sacramento County Maintenance 01/20/1994 Moderate 1,418,788 2017-2019 4.1 No 3 / 2 03/18/2002
67 FR 7082
  10/28/2013
78 FR 59261
San Bernardino County (part); excluding Searles Valley Planning area and South Coast Air Basin Nonattainment 01/20/1994 Moderate 237,418 2017-2019 1.3 No 3 / 1 03/18/2002
67 FR 7082
   
San Joaquin Valley Air Basin; Fresno, Kern, Kings, Madera, Merced, San Joaquin, Stanislaus, Tulare Counties Maintenance 11/15/1990 Serious 3,830,257 2017-2019 8.4 No 3 / 3  
 
08/19/2003 12/12/2008
73 FR 66759
Trona Nonattainment 11/15/1990 Moderate 4,167 2017-2019   Insufficient Data 3 / 0 09/05/2002
67 FR 50805
   

California PM-2.5 (1997) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(µg/m3)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Los Angeles-South Coast Air Basin Nonattainment 04/05/2005 Moderate 15,716,335 2017-2019 14.0 Yes 8 / 6 08/24/2016
81 FR 48350
   
San Joaquin Valley Nonattainment 04/05/2005 Serious 3,842,165 2017-2019 16.9 No 22 / 8  
 
   

California PM-2.5 (2006) Areas    Return to map
Area designated nonattainment for the 24-hour standard     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
24-Hr
(µg/m3)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Chico Maintenance 12/14/2009 Moderate 217,626 2017-2019 39 No 7 / 2 06/09/2017
82 FR 21711
12/18/2017 08/10/2018
83 FR 32064
Imperial County Nonattainment 12/14/2009 Moderate 154,061 2017-2019 33 Yes 7 / 2 06/09/2017
82 FR 21711
   
Los Angeles-South Coast Air Basin Nonattainment 12/14/2009 Serious 15,716,242 2017-2019 38 No 22 / 12  
 
   
Sacramento Nonattainment 12/14/2009 Moderate 2,206,060 2017-2019 54 No 10 / 2 06/09/2017
82 FR 21711
   
San Francisco Bay Area Nonattainment 12/14/2009 Moderate 6,971,067 2017-2019 48 No 7 / 2 06/09/2017
82 FR 21711
   
San Joaquin Valley Nonattainment 12/14/2009 Serious 3,842,165 2017-2019 64 No 23 / 17  
 
   
Yuba City-Marysville Maintenance 12/14/2009 Moderate 164,955 2017-2019 32 Yes 6 / 5 02/11/2013
78 FR 2211
05/23/2013 01/08/2015
79 FR 72981

California PM-2.5 (2012) Areas    Return to map     Top of page

Click on the Area name
to view SIP Required Elements


Area
Status Designation
Date
Classification 2010
Population
(state portion)
Meets NAAQS
Basis
Design Value
Annual
(µg/m3)
(entire area)
Meets
NAAQS
SIP
Requirements
Original/
Approved
Clean Air
Determination
Citation
Effective Date
Click to view
FR notice
Redesignation
Request Date
Redesignation
Citation
Effective Date
Click to view
FR notice
Imperial County Nonattainment 04/15/2015 Moderate 154,061 2017-2019 12.0 Yes 7 / 1  
 
   
Los Angeles-South Coast Air Basin Nonattainment 04/15/2015 Serious 15,716,242 2017-2019 14.0 No 14 / 7  
 
   
Plumas County Nonattainment 04/15/2015 Moderate 5,843 2017-2019 14.2 No 7 / 6  
 
   
San Joaquin Valley Nonattainment 04/15/2015 Moderate 3,842,165 2017-2019 16.9 No 7 / 0  
 
   

California SO2 (1971) Areas     Return to map Top of page

No designated areas for this pollutant.

California SO2 (2010) Areas     Return to map Top of page

No designated areas for this pollutant.
We have made our best effort to ensure that the data contained in these reports is accurate. We note that there may be brief delays in updating the reports as we receive new state submissions and we take rulemaking action on plans. In order to assist us in providing accurate information, we request that you contact us by clicking on the "Contact Us" link near the top of this page with any comments regarding or corrections to the posted information, including concerns about whether the entries reflect the most recent status.

Current and historical design value data can be found on the EPA Air Quality Design Values website and the EPA Green Book contains comprehensive nonattainment area, designation status, and historical information.

The level of the 1-hour NAAQS for sulfur dioxide is 75 parts per billion (ppb) calculated as the 3-year average of the 99th percentile of the annual distribution of daily maximum 1-hour average concentrations.