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Area Designations for 1997 Ground-level Ozone Standards

Region 9: State Designations for the 1997 8-Hour Ozone Standard

Boundary Designations for the 1997 8-Hour Ozone Standard - EPA Region 9
(as of September 18, 2009)

Map showing designations for region 9 map legend

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This table identifies all counties EPA has designated as nonattainment. In some cases EPA designated partial counties. These are identified by a (P). If a county is not listed below, EPA has designated it as unclassifiable/attainment. See also the table of redesignated areas.

State
Nonattainment Area Name
Counties
April 15, 2004 Classification
Maximum
Attainment Date
(from June 15, 2004)
Current/Proposed Classification Resdesignation Effective Date
Arizona 1
Phoenix -Mesa
Map (PDF) (2 pp, 55KB)
Maricopa (P)
Pinal (P)
Former Subpart 1 June 2009 Former Subpart 1
-
California 1
Los Angeles South Coast Air Basin, CA
Map (PDF) (3 pp, 118KB)
Los Angeles (P)
Orange
Riverside (P)
San Bernardino (P)
Severe-17 June 2021 Severe-17
-
Riverside Co, CA (Coachella Valley)
Map (PDF) (2 pp, 76KB)
Riverside (P) Serious June 2013 Serious
-
San Joaquin Valley, CA
Map (PDF) (2 pp, 135KB)
Fresno
Kern (P)
Kings
Madera
Merced
San Joaquin
Stanislaus
Tulare
Serious June 2013 Serious
-
Amador and Calavaras Cos (Central Mountain Counties), CA
Map (PDF) (1 p, 65KB)
Amador
Calaveras
Former Subpart 1 June 2009 Former Subpart 1
-
Mariposa and Tuolumne Cos (Southern Mountain Counties), CA
Map (PDF) (1 p, 73KB)
Tuolumne
Mariposa
Former Subpart 1 June 2009 Former Subpart 1
-
Sacramento Metro, CA
Map (PDF) (2 pp, 134KB)
El Dorado (P)
Placer (P)
Sacramento
Solano (P)
Sutter (P)
Yolo
Serious June 2013 Serious
-
Nevada (Western Part), CA
Map (PDF) (1 p, 68KB)
Nevada (P) Former Subpart 1 June 2009 Former Subpart 1
-
Los Angeles-San Bernardino Cos (W Mojave Desert), CA
Map (PDF) (2 pp, 102KB)
San Bernardino (P)
Los Angeles (P)
Moderate June 2010 Moderate
-
Ventura Co, CA
Map (PDF) (1 p, 81KB)
Ventura (P) Moderate June 2010 Serious
-
Kern Co (Eastern Kern), CA
Map (PDF) (2 pp, 58KB)
Kern (P) Former Subpart 1 June 2009 Former Subpart 1
-
San Diego, CA
Map (PDF) (1 p, 65KB)
San Diego (P) Former Subpart 1 June 2009 Former Subpart 1
-
Imperial Co, CA
Map (PDF) (1 p, 43KB)
Imperial Marginal June 2007 Moderate
-
Chico, CA
Map (PDF) (1 p, 41KB)
Butte Former Subpart 1 June 2009 Former Subpart 1
-
San Francisco Bay Area, CA
Map (PDF) (2 pp, 158KB)
Alameda
Contra Costa
Marin
Napa
San Francisco
Santa Clara
San Mateo
Solano (P)
Sonoma (P)
Marginal June 2007 Marginal
-
Sutter County (Sutter Buttes), CA
Map (PDF) (1 p, 38KB)
Sutter (P) Former Subpart 1 June 2009 Former Subpart 1
-
Hawaii entire state is attainment
Nevada 1 Las Vegas, NV 2
Map (PDF) (2 pp, 70KB)
Clark Former Subpart 1 June 2009 Former Subpart 1
-

1 Includes Tribal lands

2 See the Clark County, Nevada page for correspondence relating to the boundaries and effective date of the designation.

Region 9 Recommendations and EPA Responses

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