40 CFR § 52.1234 - Significant deterioration of air quality.
---
identifier: "/us/cfr/t40/s52.1234"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 52.1234 - Significant deterioration of air quality."
title_number: 40
title_name: "Protection of Environment"
section_number: "52.1234"
section_name: "Significant deterioration of air quality."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "52"
part_name: "APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401"
cfr_part: "52"
---
# 52.1234 Significant deterioration of air quality.
(a) The requirements of sections 160 through 165 of the Clean Air Act are met, except for sources seeking permits to locate in Indian country within the State of Minnesota.
(b) Regulations for the prevention of the significant deterioration of air quality. The provisions of § 52.21 except paragraph (a)(1) are hereby incorporated and made a part of the applicable State plan for the State of Minnesota for sources wishing to locate in Indian country; and sources constructed under permits issued by EPA.
[82 FR 44736, Sept. 26, 2017]