August 19,2014 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

Region 1 

5 Post Office Square, Suite 100 

Boston, MA 02109-3912 

The Honorable Paul LePage 

Governor of Maine 

1 State House Station 

Augusta, Maine 04333 

Dear Governor LePage: 

Thank you for your recommendation dated October 18, 2013 of air quality designations for the 20 12 

revised primary annual fine particle (PM2.s) National Ambient Air Quality Standard (NAAQS) 

throughout Maine. I appreciate the information Maine shared with the U.S. Environmental Protection 

Agency as we move forward to improve PM2.s air quality. This letter is to notify you of the EPA's 

preliminary response to Maine's recommendation and to inform you of our approach for completing 

the initial area designations for the 2012 revised primary annual PM2.s standard. 

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. The EPA revised the primary annual 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 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 of PM2.s-related 

adverse health effects, including premature mortality, increased hospital admissions and emergency 

department visits, and development and exacerbation of chronic respiratory disease. 

History 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 of this routine process, the EPA is working with the states and tribes to identify areas in the 

country that meet the standards and those that need to take steps to reduce PM2.s air pollution. Within 

one year of promulgating a new or revised air quality standard, the Clean Air Act requires the 

Governor of each state to submit to the EPA a list of all areas in the state, with a designation 

recommendation for each area. As a first step in implementing the 2012 annual PM2.s standard, 

Governors were to submit their designation recommendations, including appropriate area boundaries, 

by December 13, 2013. 
2 

As required by the Clean Air Act, the EPA then promulgates designations for all areas across the 

country. The EPA designates an area as "nonattainment" if it is violating the 2012 annual PM2.s 

NAAQS or if it is contributing to a violation of the 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 reason to 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 whether the area is meeting the NAAQS or where 

EPA has not determined that the area contributes to a nearby violation. At this 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 Maine on October 

18, 2013 and have reviewed the relevant technical information, including 2011- 2013 air quality data. 

These data do not indicate any violation of the 2012 annual PM2.s NAAQS in Maine or contribution to 

any nearby area. Accordingly, the EPA intends to designate the entire state of Maine as 

unclassifiable/attainmcnt. 

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-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 of 2014. 

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

PM2.5 air 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 have any questions, please do not hesitate to contact me, or have your staff 

contact Alison Simcox of my stafT at 617-918-1684 or simcox.alison@epa.gov. 

cc: Patricia Aho, ME DEP Commissioner 

Marc Cone, Director, Bureau of Air Quality 

116urt s 1 

Spalding, 

Regional Administrator, 

EPA New England. 

Janet G. McCabe, Acting Assistant Administrator for Air and Radiation 

Stephen D. Page, Director, Office of Air Quality Planning and Standards