{"data":{"id":"us/40-cfr-52.1523","jurisdiction":"us","citation":"40 CFR 52.1523","heading":"Attainment dates for national standards.","body":"The following table presents the latest dates by which the national standards are to be attained. The dates reflect the information presented in New Hampshire's plan.\nAir quality control region SO 2 PM 10 NO 2 CO O 3\nPrimary Secondary\nNH portion Andoscoggin Valley Interstate AQCR 107 a b a a a a\nCentral NH Intrastate AQCR 149 a b a a a a\nNH portion Merrimack Valley-Southern NH Interstate 121:\nBelknap County a b a a a a\nSullivan County a b a a a a\nCheshire County a b a a a d\nPortmouth-Dover-Rochester area (See 40 CFR 81.330) a b a a a e\nNH portion Boston-Lawrence-Worcester area (See 40 CFR 81.330) a b a a a f\nManchester area (See 40 CFR 81.330) a b a a a c\na. Air quality levels presently below primary standards or area is unclassifiable.\nb. Air quality levels presently below secondary standards or area is unclassifiable.\nc. November 15, 1993.\nd. November 15, 1995.\ne. November 15, 1999.\nf. November 15, 2007.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER C—AIR PROGRAMS","PART 52—APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS","Subpart EE—New Hampshire"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"67ca06641476fe1d61baa6ce907c7b18422d616a538e7937b262ec57c1e6f757","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-52.1522","next":"us/40-cfr-52.1524"},"notice":"GroundRules: Original legal text. Not legal advice."}