40 CFR § 81.101 - Metropolitan Dubuque Interstate Air Quality Control Region.

---
identifier: "/us/cfr/t40/s81.101"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 81.101 - Metropolitan Dubuque Interstate Air Quality Control Region."
title_number: 40
title_name: "Protection of Environment"
section_number: "81.101"
section_name: "Metropolitan Dubuque Interstate Air Quality Control Region."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "81"
part_name: "DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES"
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,"
regulatory_source: "36 FR 22421, Nov. 25, 1971, unless otherwise noted."
cfr_part: "81"
---


# 81.101 Metropolitan Dubuque Interstate Air Quality Control Region.

The Metropolitan Dubuque Interstate Air Quality Control Region (Illinois-Iowa-Wisconsin) consists of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial area of all municipalities (as defined in section 302(f) of the Clean Air Act, 42 U.S.C. 1857h(f)) geographically located within the outermost boundaries of the area so delimited):

In the State of Illinois: Jo Daviess County.

In the State of Iowa: Clayton County, Dubuque County, Jackson County.

In the State of Wisconsin: Grant County.