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

## DEe02 2015 Mr. Weldin Ortiz Franco Executive Director Puerto Rico Environmental Quality Board P.O. Box 11488 Santurce, PR 00910 Dear Mr. Ortiz Franco: This is in response to the 2015 Five Year Assessment and Annual Monitoring Network Review Plan dated June 4,2015, for Puerto Rico's ambient air monitoring program which you submitted to the United States Environmental Protection Agency (EPA). This is to inform you that the EPA Region 2 office has reviewed Puerto Rico's Plan for consistency with 40 CFR Part 58.10. The portion ofthe Plan involving the National Core multi-pollutant (NCore) monitoring station is subject to approval by the EPA Administrator. Accordingly, we will forward that portion ofPuerto Rico's Plan to the EPA's Office ofAir Quality Planning and Standards for review. My staff will be working closely with our Headquarters counterparts and will keep your staff informed ofthe review progress on that portion ofthe Plan. In this 2015 Plan, Puerto Rico proposes to make the following changes to its network:

• Establish one new Total Suspended Particulates lead filter monitor at Guayanilla; • Establish the PM2.5Speciation monitor atthe NCore site; • Establish a PM2.5continuous monitor at Ponce to be used for the Air Quality Index; • Closure ofthe N02 and PM2.5continuous monitors at Catano (720330008); • Reduce the sampling frequency ofthe PMro monitor located at Guaynabo from daily to 1 in 3 days; • Replace existing PM2.5filter-based Federal Reference Method (FRM) monitors with continuous Federal Equivalent Method (FEM) monitors atthe N02 near-road site required in Core Based Statistical Areas (CBSA) of2.5 million or more persons (Metropista); • Establish a new S02 monitor at Guayanilla in accordance with the regulations for the new I-hour standard; • Locate anew CO monitor with the N02 near-road monitor required in CBSAs of2.5 million or more persons; and, . • Establish the new near road N02 sites in Caguas and Ponce.

Internet Address (URL). http://www.epa.gov RocyclodlRecyclable • Printed with Vegetable 011 Based Inks on Recycled Paper (Minimum 50% Postconsumer content)The EPA Region 2 office concurs with the proposed network changes described above as well as the

PREQB's ongoing efforts with the new Caguas N02 near roadway site, with four caveats:

• Inthe 2014 Annual Network Review Plan, the PREQB proposed relocating the S02 monitor from Juncos to Guayanilla. The EPA approved the 2014 Plan on October 29,2014. Please complete this change; • The EPA suggests relocating an existing CO monitor to one ofthe new near roadway sites, preferably the Buchanan Metropista site, instead oflocating anew CO monitor with the N02 near-road monitor at Caguas; • Ifpossible, prior to replacing the existing PM2.5FRM monitors with PM2.5FEM monitors, the EPA suggests collocating the FEM monitors with the FRM monitors for at least 6months before the complete conversion to FEMs; and, • The EPAis re-evaluating the regulations in regards to N02 near road monitoring sites at CBSAs having 500,000 or more persons (inthis case, Ponce). Accordingly, until the regulations are revised, please hold offon siting activities forthe Ponce N02 near road monitor. Ifyou have any questions, please have your staff contact Mr. Karl Mangels at 212-637-4078 orMs. Mazeeda Khan at 212-637-3715. Sincerely, 

# /~£ John Filippelli, Director Clean Air and Sustainability Division cc: L. Femandez-Fontan, PREQB