40 CFR 81.12 : Protection Of Environment (§ 1.1 To Parts 1851-1899) — (§ 81.1 To Appendix A To Part 81) — Environmental Protection Agency (Continued) (§ 81.1 To Appendix A To Part 81) — Air Programs (Continued) (§ 81.1 To Appendix A To Part 81) — Designation Of Areas For Air Quality Planning Purposes (§ 81.1 To Appendix A To Part 81) — Designation Of Air Quality Control Regions (§ 81.11 To § 81.276) — National Capital Interstate Air Quality Control Region (District of Columbia, Maryland, and Virginia).

The National Capital Interstate Air Quality Control Region (District of Columbia, Maryland, and Virginia) consists of the territorial area encompassed by the boundaries of the following jurisdictions (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);

District of Columbia

In the State of Maryland: Montgomery County; Prince Georges County.

In the State of Virginia: Arlington County; Fairfax County; Loudoun County; Prince William County.

(As so delimited, the Virginia portion of the region will include the city of Alexandria, the city of Fairfax, and the city of Falls Church.)