UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 8

Ref: 8P-AR

The Honorable Gary R. Herbert Governor ofUtah State Capitol Salt Lake City, Utah 84114

Dear Governor Herbert: 1595Wynkoop Street DENVER, CO 80202-1129 Phone 800-227-8917 http://'www.epa.gov/region08



### AUG 1 9 2014

Thankyou for your recommendations dated December 10, 2013 ofair quality designations for the 2012 revised primary annual fine particle (PM2.s) National Ambient Air Quality Standard (NAAQS) throughout Utah. I appreciate the information Utah shared withthe U.S. Environmental Protection Agency as we move forward to improve PM2.s airquality. This letter is to notify you ofthe EPA's preliminaryresponse to Utah'srecommendations and to inform you ofour approach for completing the initial area designations for the 2012 revised primary annual PM2.s standard.

On December 14, 2012, the EPApromulgated a revised primary annual PM2.sNAAQS (78 FR 3086, January 15, 2013). Inthat action, the EPA revised the primary annual PM2.s standard, strengthening it from 15.0 micrograms percubic meter (J..Lg/m3) to 12.0 J..Lg/m3; retained the existing 24-hourPM2.s standard at 35 J..Lg/m3; retained the existing 24-hourPMw(coarseparticle) standard at 150 J..Lg/m3; and retained the current suite ofsecondary PM standards. The EPArevised the primary annual PM2.s standard based on an integrated assessment ofan extensive body ofnew scientific evidence, which substantially strengthens our**bp~dy**.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 array ofPM2.s-related adverse health effects, including premature mortality, increased hospital admissions and emergency department visits, and development and exacerbation ofchronic respiratory disease.

History shows us that betterhealth and cleaner air go hand-in-hand with economic growth. Working closely with the states and tribes, the EPA is implementing the standards using a commonsense approach that improves air quality and minimizes the burden on state, local, and tribal governments. Aspart of this routine process, the EPA is working with the states and tribes to identify areas in the country that
meetthe standards and those that need to take steps to reduce PM2.s airpollution. Within one year of promulgating a new or revised air quality standard, the Clean Air Act (CAA) requires the governor of each state to submitto the EPA a list ofall areas in the state, with a designation recommendation for each area. As a first step in implementing the 2012 annual PM2.s standard,gGovernors were to submit their designation recommendations, including appropriate areaboundaries, by December 13, 2013.As required bythe CAA, the EPA thenpromulgates designations for all areas across the country. The EPA designates an area as "nonattainment" ifit is violating the 2012 annual PM2.s NAAQS orifit 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/attainment" for areas that are monitoring attainment or do not have monitors, but for which the EPA has reasonto believe are likely attainment and are not contributing to nearby violations. Additionally, the EPA intends to designate as "unclassifiable"those areas where the EPA cannot determine based on available information whetherthe area is meeting the NAAQS orwhere EPA has not determined that the area contributes to a nearbyviolation. Atthis time, the EPA is proceeding with intended initial area designations using quality-assured, certified air quality monitoring data from 2011 to 2013.

We have considered the annual PM2.s designation recommendations submitted by Utah on December 10,2013, and have reviewed the relevant technical information, including 2011-2013 air quality data. These data do not indicate any violation ofthe 2012 annual PM2.s NAAQS in Utah or contributionto any nearby area. Accordingly, the EPA intends to designate the entire state ofUtah as unclassifiable/attainment.

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 commentperiod shortly in the Federal Register. After considering the additional information we receive, the EPA plans to promulgate final annual PM2.s designations in December of2014.

The EPA is committed to working withthe states and tribes to share the responsibility ofreducing PM2.s airpollution. Current and upcoming federal standards and safeguards- including pollutionreduction rules for powerplants, vehicles, and fuels- will ensure steady progress to reduce PM2.s-forming pollution and will protectpublic health in communities across the country. We look forward to a continued dialogue withyou and your staffas we worktogetherto implementthe 2012 annual PM2.s standard. Should youhave any questions, please do not hesitate to contact me, orhave your staffcontact Crystal Ostigaard ofmy staffat (303) 312-6602 orostigaard.crystal@epa.gov.

cc: Amanda Smith, Executive Director, UDEQ Bryce Bird, Director, DAQ Regional Administrator

Janet G. McCabe, Acting Assistant Administratorfor Airand Radiation Stephen D. Page, Director, Office ofAir Quality Planning and Standards