UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX

Gregory Mendoza Governor Gila River Indian Community P. 0. Box 97 Sacaton, Arizona 85147 Dear Governor Mendoza: 75 Hawthorne Street San Francisco, CA 94105·3901


## AUG 1 9 2014 OFFICE OF THE REGIONAL ADMINISTRATOR

Thank you for your recommendation, dated November 15, 2013, ofair quality designations for the 2012 annual fine pmiicle National Ambient Air Quality Standard (2012 annual PM2
.5 NAAQS) onbehalfof the Gila River India11 Community. This letter is to notify you ofthe U
.S
.Environmental Protection Agency's (EPA) preliminary decision to agree with your recommendation and to inform you ofour approach for completing the designations
. Although your involvement is not required, we would like to invite you to further participate in the designations process and to offer you consultation. Based on yourrecommendation and otherrelevant teclmical information, including 2011-2013 air quality data, the EPA intends to designate your area ofIndian country as unclassifiable/attainment along with the sulTounding state area. Ifyou have additional information that the EPA should consider, we ask that you submit it to us by October 29, 2014. Please notify us by September 29, 2014 ifyou are interested in consulting with us regarding the designations process. When requested, consultation will be conducted in accordance with the EPA Policy on Consultation and Coordination with Indian Tribes (www.epa
.gov/tribal/consultationlconsultpolicy.htm). As background, on December 14, 2012, the EPA promulgated a revised primary annual PM2.s NAAQS (78 FR 3086, January 15, 2013).

-In that action, the EPA revised the primary annual PM2.s standard, strengthening it from 15
.0 micrograms per cubic meter (J..Lg/m3) to 12.0 j..tg/m3 ; retained the existing 24- hour PM2.s standard at 35 j..tg/m3; retained the existing 24-hour PM10 (coarse particle) standard at 150 j..tg/m3; and retained the current suite ofsecondary PM standards. The EPA revised the primary annual PM2.s standard based on an integrated assessment ofan extensive body ofnew scientific evidence, which substa11tially strengthens our body ofknowledge regarding PM2
.s-related health effects. The revised primary annual PM2.s standard will provide increased protection for children, older adults, persons with pre-existing heart and lung disease, and other at
-risk populations against an atTay ofPM2.s-related adverse health effects, including premature mortality, increased hospital admissions and emergency department visits, and development and exacerbation ofchronic respiratory disease
. As required by the Clean Air Act, the EPA promulgates designations for all areas across the country. The EPA designates an area as "nonattaimnent" ifit is violating the NAAQS or ifit is contributing to a violation ofthe NAAQS in a nearby area. Consistent with designations for previous PM2
.s standards, the EPA intends to use a designation category of"unclassifiable/attainn1ent" for areas that are monitoring attainn1ent or do not have monitors, and that the EPAhas reason to believe are likely attainment and are
Printed on Recycled Papernot contributing to nearby violations. Additionally, the EPA intends to designate as "unclassifiable" those areas where the EPA either cannot determine based on available information whetherthe area is meeting the NAAQS, or has not determined whetherthe area contributes to a nearby violation. Atthis time, the EPA is proceeding with intended initial area designations using quality-assured, ce1iified air quality monitoring data from 2011 to 2013. The EPA will make its preliminary designation decisions and supporting documentation available to the general public for review and comment. We will be announcing a 30-daypublic comment period shortly in the FederalRegister. After considering additional information we receive, the EPAplans to promulgate final annual PM2.s designations in December of2014. The EPA is committedto working with the states and tribes to share the responsibility ofreducing PM2.s air pollution. Current and upcoming federal standards and safeguards- including pollution reduction rules for powerplants, vehicles, and fuels- will assure steady progress to reduce PM2.s-forming pollution and will protectpublic health in communities across the country. We look forward to working together with you and your staffto implement the 2012 annual PM2.5 NAAQS. Ifyour Tribe is interested in consultation orparticipating in further discussions or meetings with the EPA officials about the designations process, please contact me or have your staffcontact Kerry Drake ofmy staffat 415- 947-4157, or drake.kerry@epa.gov. Sincerely,

Jared Blumenfeld

cc: Ondrea Barber, Executive Director, DEQ, Gila River Indian Community