UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 2 290 BROADWAY NEWYORK , NY 10007-1866 

## AUG 1 9 2014 The Honorabl e Alejandro J. Garcia-Padilla Governor of the Commonwealth o f Puerto Rico La Fortaleza S an Juan , Puerto Rico 00901 D e ar Go ve rnor G arci a-Padill a : This letter is in re sponse to the re commendation f rom Chairwoman Laura M. Vel ez -V e lez dated D ecemb er 16 , 2013 regarding air qu ality designations for the 2012 re v i se d primary amm al fin e p a rticl e (PM 2 s) National Ambi ent Air Qu ality Standard (NAAQS) throughout Pu erto Rico
. I appre ciate the information Puerto Rico shared with the U.S. Environmental Protection Agenc y as we move forw ard to improve PM 2
.s air quality
. This letter is to notify you of the EPA ' s preliminary respons e to Puerto Rico's recomm endation and to inform you of our approach for completing the initial are a d es ignations for the 2 012 re v ised primary annual PM 2.s standard. On December 14 , 2012 , the EPA promulgated a revised primary annual PM 2
.s NAAQS (78 FR 3086 , January 15 , 2013 )
. In that action , the EPA revised the primary annual PM 2
.s s tandard , s trengthening it from 15.0 micrograms per cubic meter (!lg/m 3 ) to 12
. 0 11g/m 3 ; retained the existin g 24-hour PM 2
.s stand ard at 35 11g/m 3 ; retained the existing 24-hour PM10(coarse particle) standard at 150 11 g/m 3 ; and retained the curre nt 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 sci entific evidence , which substantially strengthens our body of knowled ge regarding PM 2
.s-related health effects. The re v ised primary annual PM 2
.s standard will provide incre ased protection for children , older adults , persons with pre-exi stin g 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 trib al government s . As part of this routine process , the EPA is working with the states and tribes to identif y are a s in the country th at meet the standards and those that need to take steps to reduce PM 2 .s air pollution
. Within on e ye ar of promulgating a new or revised air quality stand ard , the Clean Air Act require s th e Gov e rnor of e ac h state to submit to the E PA a list of all areas in the state , with a designation re commend ation f or eac h are a . As a first step in implementing the 2012 annual PM 2
.s standard , Go ve rn or s we re to submit th eir design ation recommendations , including appropriate area boundaries , b y D ec emb er 1 3, 2013
.

Internet Address (URL) • http ://www

. epa . gov Recycled/Recyclable •Printed with Vegetable Oil Based Inks on 100% Postconsumer, Process Chlorine Free Recycled PaperAs required by the Cle an A ir 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 PM z.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. Sincere ly , 

# 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