Air Resources BoardMary
D. Nichols, Chairman1001IStreet•P.O.Box2815MatthewRodriquezSacramento,California95812www.arb.ca.govEdmundG.BrownJr.SecretalyforGovernorEnvironmentalProtection November26, 2012 Mr. Jared Blumenfeld Regional Administrator U.S. Environmental Protection Agency Region

9 75 Hawthorne StreetV San Francisco, California 94105 Dear Mr. Blumenfeld: With this letter, the Air Resources Board (ARB
or Board)

is requesting parallel processing

of the 2012 Redesignation Request and Maintenance
Plan for the 1997 National Ozone Standard
for San Diego County (Maintenance Plan), for which the Board will consider approval

at a public hearing

to be held on December

6, 2012.

If approved, ARB will submit the Maintenance
Plan to the U.S. Environmental Planning Agency (U.S. EPA) for approval

as a revision

to California’s State Implementation
Plan (SIP). ARB

is requesting parallel processing

to help ensure that U.S. EPA can act on the Maintenance
Plan before the 1997 8-Hour Ozone National Ambient
Air Quality Standard (NAAQS)

is rescinded. ARB staff has coordinated
with your staff on this request. On June 13, 2012, U.S. EPA classified San Diego County
as a “Moderate” nonattainment
area for the 1997 8-hour Ozone NAAQS, requiring

a SIP addressing Moderate area control requirements

to be submitted

to U.S. EPA by June 13, 2013. More recent data show that San Diego attained the NAAQS

in 2011. The San Diego Air Pollution Control District’s (District) Maintenance
Plan demonstrates

that the region’s
air quality will continue

to meet the NAAQS through

at least 2025. The District’s Governing Board

is scheduled

to consider adoption

of the Maintenance Plan on December

5, 2012. ARB staff has reviewed
the Maintenance
Plan as proposed by the District staff on November

2, 2012, and finds that the Maintenance
Plan meets
all applicable Clean Air Act requirements

for redesignation requests and maintenance plans and demonstrates

that ozone levels

in the San Diego area will continue

to meet the 1997 8-hour ozone NAAQS. Based
on staff’s review, we will recommend
that the Board approve the Maintenance
Plan for submittal

to U.S. EPA as
a SIP revision.

If approved

by U.S. EPA, the Maintenance
Plan will fulfill all applicable
SIP requirements for the 1997 8-Hour Ozone Standard.TheenergychallengefacingCaliforniaisreaLEveryCalifornianneedstotakeimmediateactiontoreduceenergyconsumption.Foralistofsimplewaysyoucanreducedemandandcutyourenergycosts,seeourwebsite:http://www.arb.ca.gov. California Environmental Protection AgencyPrintedonRecycledPaperJared Blumenfeld November

26, 2012 Page

2 This package contains copies
of the following materials. I. ARB Notice
of Public Meeting

to Consider
the Approval

of the San Diego 8-Hour Ozone Redesignation Request and Maintenance Plan, dated November

14, 2012; II. San Diego County Air Pollution Control District’s 2012 Redesignation Request and Maintenance Plan for the 1997 National ozone Standard; and Ill. ARB Staff Report, Analysis

of the San Diego County Air Pollution Control District 2012 Redesiqnation Request and Maintenance Plan for the 1997 National ozone Standard, dated October
26, 2012. If you have any questions, please call Ms. Lynn Terry, Deputy Executive Officer,

at (916) 322-2739,

or have your staff contact Mr. Douglas
Ito, Chief, Air Quality and Transportation Planning Branch,

at (916) 322-0285. Sincerely, Enclosures cc: See next page.JaredBlumenfeldNovember26,2012Page3cc:(w/oenclosures)Ms.DeborahJordanDirector,AirDivisionU.S.EnvironmentalProtectionAgencyRegion975HawthorneStreetSanFrancisco,California94105Mr.RobertKardAirPollutionControlOfficerSanDiegoCountyAirPollutionControlDistrict10124OldGroveRoadSanDiego,California92131Mr.RobertReiderSupervisor,PlanningandRuleDevelopmentSanDiegoCountyAirPollutionControlDistrict10124OldGroveRoadSanDiego,California92131Ms.LynnTerryDeputyExecutiveOfficerExecutiveOfficeMr.DouglasIto,ChiefAirQualityandTransportationPlanningBranch