Regulation 7

I.

I. Applicability

This section is a historical timeline showing when different ozone air quality designations took effect in the Denver Metro Area and North Front Range, starting in 1978 and running through 2021, including changes from nonattainment to maintenance status and updates to different ozone standards (1-hour and 8-hour). The most recent change in 2021 expanded the 8-hour ozone nonattainment area to include part of northern Weld County.

I.A.1.b.

I.A.1.b. (State Only) All provisions of this regulation apply to any ozone nonattainment

All provisions of Regulation 7 apply to any area in Colorado designated as nonattainment for ozone (whether under the 1-hour or 8-hour ozone standard), unless a specific exception is noted in Section I.A.1.c. You can find maps and timelines showing which Colorado areas are ozone nonattainment or maintenance areas in Appendix A of this regulation.

I.A.1.c.

I.A.1.c.

Part B Sections II through VIII (except VI.E.) apply to all oil and gas operations anywhere in Colorado. However, these sections are only enforceable by the state of Colorado, not by the federal EPA, unless specifically noted otherwise in the regulation.

II.

II. General Provisions

This provision simply lists the geographic areas in Colorado that are subject to federal ozone air quality standards - specifically the Denver Metro Area, North Front Range, and northern Weld County. It references both the 2008 and 2015 versions of the National Ambient Air Quality Standards (NAAQS) for ozone, which set limits on ground-level ozone pollution. If your oil and gas operations are located in these areas, you'll need to comply with stricter air quality rules designed to reduce ozone-forming emissions.

II.A.1.

II.A.1. “8-Hour Ozone Control Area” means the Counties of Adams, Arapahoe, Boulder

The "8-Hour Ozone Control Area" is a defined geographic region that includes Adams, Arapahoe, Boulder, Douglas, and Jefferson counties, the Cities and Counties of Denver and Broomfield, part of Rocky Mountain National Park, and certain portions of Larimer and Weld counties. This is just a definition that establishes which areas are subject to stricter ozone-related requirements elsewhere in the regulation.