### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Region 1
August 19, 2014 The Honorable Margaret Wood Hassan Governor ofNew Hampshire State House Concord, New Hampshire 03301 Dear Governor Hassan: 

### 5 Post Office Square, Suite 100 Boston, 

### MA 0 2 109 -391 2

Thank you for your recommendation dated February 19, 201 4 of air quality designations for the 2012 revised primary annual fine particle (PM2.s) National Ambient Air Quality Standard (NAAQS) throughout New Hampshire. I appreciate the information New Hamp shire shared with the U.S. Environmental Protection Agency as we move forward to improve PM2.s air quality. This letter is to notify you ofthe EPA's preliminary response to New Hampshire's recommendation and to inform you of our approach for completing the i ni tia l area designations for the 2012 revised primary annual PM2 . s sta ndard. 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

**(~g/m )**  

### to 12.0

**g/m ;**  

### retained the existing 24-hour PM2 .s standard at 35

**~g/m ;**  

### retained the existing 24-hour PM10(coarse particle) standard at 150

**~g/m ;**  

### and retained the current suite of secondary PM standards. T he EPA revised the primary arumal PM2 . s standard based on an integrated assessment of an extensive body of new scientific evidence, which substantially strengthens our body of knowledge regarding PM2 .s -related health effects. The revi sed primary annual PM2 .s standard will provide increased protection for children, o lder adults, persons with pre-existing heart and lung disease, and other at-risk populations against an array of PM2 .s -related adverse health effects, including premature mortality , increased hospital admissions and emergency department visits , and development and exacerbation ofchronic respiratory disease. Hist<>ry shows us that better health 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. As part <?fthis routine process, the EPA i s working w ith the states and tribes to identity areas in the country that meet the standards and those that need to take steps to reduce PM2 .s air pollution . Within one year ofpromulgating a new or revised air quality standard, the Clean Air Act requires the Governor ofeach state to submit to the EPA a li st of all areas in the state, with a designation recommendation for each area. As a first step in implementing the 2012 annual PM2 .s standa rd, Governors were to submit their designation recommendations , including appropriate area boundaries, by December 13 ,2013.2 i\s required by the Clean i\ir Act, the EPA then promulgate s designations for all areas across the country. The EPA des ignates an area as "nonattainment" if it is violating the 2012 annual PM2 . s NAAQS or i f it is contr ibuting to a violation of the NAAQS in a nearby area. Co ns i stent with des ignations for previous PM2.s standards, the EPA intends to use a designation category of " unclassifiable / attainment" for areas that arc monitoring attainment or do not have monitors, but for which the EPA has reason to believe are likely attainment and are not contributing to nearby v iola ti ons. Additionally , the EPA inte nds to designate as "unclassifiable" those areas where the EPA cannot determine based on availab le information whether the area is meeting the NAAQS or where EPA ha s not determined that the area contributes to a nearby vio lation. At this time, the EPA is proceeding with intended initial area designations using quality-assu red, certified air quality monitoring data from 2011 to 2013. We have considered the annual PM2 .s designation recommendations submitted by New Hampshire on February 19 ,2014 and have reviewed the re levant technical information, including 20 1 1-20 1 3 air quality data. These data do not indicat e any vio lation of the 2012 annual PM2.s NAAQS in New Hampshire or contribution to any nearby area. Accordingly, the EPA intend s to designate the entire state ofNew Hampshire as unclassifiable /attai nment. The EPA will make its preliminary designation decisions and supporting documentation available to the general p ubli c for review and comment. We w ill be announcing a 30-day public comment period 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 i s committed to working with the states and tribes to s h are the responsibility of reducing PM2.5 a ir pollution. Current and upcoming federal standards and safeguards - including pollution reduction rules for power plants, vehicles, and fuels -will ensure steady progress to reduce PM2 .sforming pollution and will protect public health in communities across the country. We look forward to a continued dialogue with you and your staff as we work together to implement the 2012 annual PM2 .s standard. Should you ha ve any questions , please do not hesitate to contact me , or have your staff contact Alison Simcox ofmy staff at 617 - 918-1684 or simcox.alison@epa.gov.

cc: Tom Burack, NH DES Commissioner 

# !;jf jj)/ H. Curtis S palding, Regional Administrator, EPA New England . Craig Wright, Director, Air Resources Division Janet G. McCabe , Acting Assistant Administrator for Air and Radiation S tephen D. Page, Director, Office of Air Quality Planning and Standards