UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION 2 

290 BROADWAY 

NEWYORK, NY 10007-1866 

AUG 1 9 2014 

The Honorable Alejandro J. Garcia-Padilla 

Governor of the Commonwealth of Puerto Rico 

La Fortaleza 

San Juan, Puerto Rico 00901 

Dear Governor Garci a-Padilla: 

This letter is in response to the recommendation from Chairwoman Laura M. Velez-Velez dated 

December 16, 2013 regarding air quality designations for the 2012 revised primary ammal fine particle 

(PM2 s) National Ambient Air Quality Standard (NAAQS) throughout Puerto Rico. I appreciate the 

information Puerto Rico 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 Puerto Rico'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 (!lg/m3

) to 12.0 11g/m3; retained the existing 24-hour PM2.s 

standard at 35 11g/m3

; retained the existing 24-hour PM10(coarse particle) standard at 150 11g/m3

; 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 airgo 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 . 

Internet Address (URL) • http://www.epa.gov 

Recycled/Recyclable •Printed with Vegetable Oil Based Inks on 100% Postconsumer, Process Chlorine Free Recycled Paper 
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 PMz s NAAQS 

or if it is contributing to a violation of the NAAQS in a nearby area. Consistent with designations for 

previous Pl'vhs 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. 

After considering Puerto Rico 's December 16, 2013 annual PMz.s designation recommendation and 

other relevant technical information, including 2011-2013 air quality data, the EPA agrees with Puerto 

Rico's recommendation and intends to designate the entire Commonwealth of Puerto Rico as 

unclassifiable. A Technical Support Document, which provides additional detail regarding the status of 

data for Puerto Rico and the rationale to support the EPA's unclassifiable designation, is available on the 

EPA's website at http://www.epa.gov/pmdesignations/'7012standards/state.htm 

If Puerto Rico has additional information for the EPA to consider, please submit it to us by October 29, 

2014. 

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 PMz.s designations in December of2014. 

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

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 PMz s-forming 

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 PMz.s 

standard. Should you have any questions, please do not hesitate to contact me, or have your staff contact 

Richard Ruvo of my staff at (212) 637-4014 or ruvo.richard@epa.gov. 

Sincerely, 

lhlr-r-7/. ~/YIJz__ 

Judith A. Enck 

Regional Administrator 

cc: Laura M. Velez-Velez, Puerto Rico Environmental Quality Board 

Eliud Gerena, Puerto Rico Environmental Quality Board 

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

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