40 CFR § 51.1204 - Enforceable emission limits providing for attainment.

---
identifier: "/us/cfr/t40/s51.1204"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 51.1204 - Enforceable emission limits providing for attainment."
title_number: 40
title_name: "Protection of Environment"
section_number: "51.1204"
section_name: "Enforceable emission limits providing for attainment."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "51"
part_name: "REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "23 U.S.C. 101; 42 U.S.C. 7401-7671q."
regulatory_source: "36 FR 22398, Nov. 25, 1971, unless otherwise noted."
cfr_part: "51"
---


# 51.1204 Enforceable emission limits providing for attainment.

At any time prior to January 13, 2017, the air agency may submit to the EPA federally enforceable SO<sub>2</sub> emissions limits (effective no later than January 13, 2017) for one or more applicable sources that provide for attainment of the 2010 SO<sub>2</sub> NAAQS in the area affected by such emissions. The submittal shall include associated air quality modeling and other analyses that demonstrate that all modeling receptors in the area will not violate the 2010 SO<sub>2</sub> NAAQS, taking into account the updated allowable emission limits on applicable sources as well as emissions limits that may apply to any other sources in the area. The air agency shall not be subject to the ongoing data requirements of § 51.1205 for such area if the air quality modeling and other analyses demonstrate that the area will not violate the 2010 SO<sub>2</sub> NAAQS.