Citation

77 FR 11739

Canonical document for this Federal Register citation.

Approval and Promulgation of Air Quality Implementation Plans; District of Columbia, Maryland, and Virginia; Determinations of Attainment of the 1997 8-Hour Ozone National Ambient Air Quality Standard for the Washington, DC-MD-VA 8-Hour Ozone Moderate Nonattainment Area Tuesday, February 28, 2012 77 FR 11739