UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX 75 Hawthorne Street San Francisco, CA 94105-3901

OFFICE OFTHE 

## DEC 0 9 

## 2011 REGIONAL ADMINISTRATOR The Honorable Edmund G. Brown, Jr. State ofCalifornia State Capitol Building, Suite 1173 Sacramento, California 95814

Dear GovernorBrown:

Thank you for your recommendations dated March II, 2009 and October 12, 2011 on air quality designations for the revised 2008 National Ambient Air Quality Standards for ozonethroughout California. I appreciatethe information California shared with the U.S. EnvironmentalProtection Agency as we move forward to improve ozone air quality. Thepurpose ofthis letter is to notify you of the U.S. Environmental Protection Agency's preliminary decision to designate 16 areas ofCalifornia

as nonattainment for the revised 2008 ozoneNAAQS, to inform you that we intend to modify several ofyourrecommendations (as noted in Enclosure I) and to inform you ofour approach for completing the designations for the revised ozone NAAQS.

On March 12,2008,the EPA revised its NAAQS for ground-level ozoneto provide increased protection ofpublic health and the environment. The EPA lowered the primary 8-hour ozone standard from 0.08 parts permillion (ppm) to 0.075 ppm to protect against health effects associated with ozone exposure, including a range ofserious respiratory illnesses and increased premature death from heart

or lung disease. The EPA revised the secondary 8-hour ozone standard, making it identical to the primary standard, to protect against welfare effects, including impacts on sensitive vegetation and forested ecosystems.
History shows us that betterhealth and cleaner air go hand-in-hand with economic growth. Working closelywith the states and tribes, the EPA is implementingthe standards using a common sense approach that improves air quality and minimizes the burden on state and local governments. As part ofthis routine process, EPA is working with the states to identify areas in the countrythat meet the standards and those that need to take steps to reduce ozonepollution. Within one year after a new or revised air quality standard is established, the CleanAir Actrequires the Governor ofeach state to submitto the EPA a list ofall areas in the state, with recommendations for whether each area meets the standard.

As a first step in implementing the 2008 ozone standards, the EPA asked states to submittheir designation recommendations, including appropriate area boundaries, by March 12,2009. In September2009, the EPA announced it was reconsidering the 2008 ozone standards. The EPA latertook steps to delay the designationprocess for the 2008 ozone standardspending outcome ofthe reconsideration. However, in September 2011, the Office ofManagement and Budget returned to EPA the draftfinal**ru~e** addressinl5. the reconsideration ofthe 2008standards. On September

### 22 

### 2011 th EPA restarted the implementation effort by issuing.a memorandum to clarify for state and lo'cal

### ag~nc~es the status ofthe 2008 ozone standards and to outlme plans for moving forward to implementthem. The EPA

Printedon Recycled Paperindicated that it would proceed with initial area designations for the 2008 standards, and planned to use the recommendations states made in 2009 as updated by the most current, certified air quality data from 2008­ 2010. While the EPA did not request that states submit updated designation recommendations, the EPA provided the opportunity for states to do so. Thank you for the October 12,2011 updated designation recommendation from California based on the assessment of2008-2010 and preliminary 2009-2011 air quality data.

As required by the Clean Air Act, the EPA will designate an area as nonattainment ifit is violating the 2008 ozone standards or contributing to a violation ofthe standards in a nearby area. Consistent with designations for previous ozone standards, the EPA intends to designate an area as unclassifiable/attainment ifthere are certified, quality-assured air quality monitoring data showing the

area is meeting the ozone standards orthere are no monitoring data for the area, and the EPA has not made a detennination that the area is contributing to a violation in a nearby area.

After considering California's October 12,2011 ozone designation recommendations, which were based on both 2008-2010 as well as preliminary2009-2011 airquality data, as well as other relevant technical infonnation, the EPA intends to designate the areas listed in Enclosure 1 as nonattainment. The enclosed Technical SupportDocumentprovides a detailed analysis to support ourpreliminary decisions. TheEPA intends to designate all otherareas ofthe state as unclassifiable/attainment. In order for the EPA to consider2009-2011 airquality data in the final designation decisions for any area, California must submit certified, quality-assured 2009-2011 air quality monitoring data for the area to the EPA by February 29,2012.

The EPA will continue to work with state officials regarding the appropriate boundaries for the nonattainment areas in California. IfCalifornia has additional infonnation that you would like the EPA to consider, please submit it to us by February29,2012. TheEPA will also make its preliminary designation decisions and supporting documentation available to the general public for review and comment. We will be announcing a 30-daypublic commentperiod shortly in the 

### FederalRegister. After considering additional infonnation we receive, the EPA plans to promulgate final ozone designations in the spring of2012.

The EPA is committed to working with the states and tribes to share the responsibility ofreducing

ozone air pollution. Current and upcoming federal standards and safeguards, including pollution reduction rules for power plants, vehicles and fuels, will assure steady progress to reduce ozonefonning pollution and will protectpublic health in communities across the country. We look forward to

a continued dialogue with you and your staffas we worktogether to implement the 2008 ozone standards. Should you have any questions, please do nothesitate to contact me or AmyZimpfer, Associate Director, Air Division, ofmy staffat 415-947-4146 or zimpfer.amy@epa.gov.
Sincerely, 

# h

Jared Blumenfeld

Enclosurescc: (with full enclosures)

Matthew Rodriquez, Secretary, CaliforniaEnvironmental Protection Agency MaryNichols, Chairman, CaliforniaAirResources Board James Goldstene, Executive Officer, California AirResources Board Lynn Terry, DeputyExecutive Officer, California AirResources Board

cc: (with area-specific enclosures)

Affected AirPollution Control Officers

cc: (enclosure 1only)

Affected Tribal Leaders and Tribal Environmental Coordinators

cc: (via electronic correspondence)

Gina McCarthy, Assistant Administrator for Air and Radiation Stephen D. Page, Director, Office ofAir QualityPlanning and Standards

### Area Nonattamment Lounues**~UWllll;;:>** 

### Amador and Calaveras Counties (Central Mountain Counties)* Calaveras County Amador County and 

### Calaveras County Chico (Butte 

### County)* Butte County Butte County Imperial County* Imperial County Imperial County Kern County (Eastern Kern, excluding Indian Wells Valley) Kern County (Eastern Kern, excluding Indian Wells Valley) Kern County (Eastern Kern, excluding Indian Wells Valley)

Los Angeles-San Bernardino (West Mojave Desert)* San Bernardino County (Mojave DesertAir Basinportion) as a separate nonattainment area from Los Angeles County (Antelope Valleyportion or Mojave.Desert AirBasinportion) nonattainment

area San Bernardino County (Mojave DesertAir Basin portion), and Los Angeles County (Antelope Valley portion or Mojave DesertAir Basin portion)



### Los Angeles-South CoastAir Basin* Los Angeles County (South CoastAir Basin portionwhich includes Santa Catalina and San Clemente Islands), Orange County, SanBernardino County (South CoastAir Basinportion), Riverside County (South Coast Air Basin portion) Los Angeles County (South CoastAir Basinportion which includes Santa Catalina and San Clemente Islands), Orange County, San Bernardino County (South Coast Air Basin portion), Riverside County (South Coast AirBasin portion) Mariposa and Tuolumne Counties (Southern Mountain Counties)* Mariposa County Mariposa County and Tuolumne County


### Nevada Countv(Westernpart) Nevada County (Western part) Nevada County (Western part)

Tuscan Buttes Tehama County (Tuscan Buttes portion, above 1,800 feet elevation) Tehama County (Tuscan Buttes portion, above 1,800 feet elevation)

Riverside County (Coachella Valley)* Riverside County (Salton Sea Air Basinportion) Riverside County (Salton Sea AirBasinportion)

Sacramento Metro* Sacramento County, Yolo County, Solano County (Sacramento ValleyAir Basin portion), Sutter County (southern portion), EI Dorado County (Sacramento ValleyAirBasinportion), Placer County (Sacramento ValleyAir Basin portion) Sacramento County, Yolo County, Solano County (Sacramento Valley Air Basin portion), Sutter County (southern portion), £1 

### Dorado County (Sacramento ValleyAirBasin portion), Placer County (Sacramento Valley Air Basin portion) San Diego County* San Diego County San Diego County
San Francisco BayArea* San Francisco County, Marin County, San Francisco County, Marin County,southern Sonoma County (San Francisco BayAirBasin portion), Napa County, western Solano County (San Francisco BayAirBasin portion), Contra Costa County, AlamedaCounty, Santa ClaraCounty, San Mateo County southern SonomaCounty (San Francisco BayAir Basin portion), Napa County, western Solano County(San Francisco BayAirBasin portion), Contra Costa County, Alameda County, Santa Clara County, San Mateo County

San Joaquin Valley* San Joaquin County, Stanislaus County, Merced County, Madera County, Fresno County, Kings County, Tulare County, Kern County (San Joaquin Air Basin portion) San Joaquin County, Stanislaus County, Merced County, Madera County, Fresno County, Kings County, Tulare County, Kern County (San Joaquin Air Basin portion) San Luis Obispo (Eastern San Luis Obispo) SanLuis Obispo County (Eastern San Luis Obispo) San Luis Obispo County (Eastern San Luis Obispo)

Ventura County (continental portion) Continental portion ofVentura County (excludes Anacapa and SanNicolas islands) Continentalportion ofVentura County (excludes Anacapa and SanNicolas islands) EPA intended modifications to state recommendations are shown In bold. *Indicates multi-jurisdictional nonattainment area or areas that include tribal lands. Table 1, contained in the Technical Analysis section ofeach nonattainment area discussion in the enclosed Technical Support Document, identifies the tribal lands that EPA intends to designate as part ofthe nonattainment area.

### ENCLOSURE 2

Technical SupportDocument