Approval and Promulgation of Air Quality Implementation Plans; District of Columbia, Maryland, Virginia, and West Virginia; Determinations of Attainment of the 1997 Fine Particle Standard for the Metropolitan Washington and Martinsburg-Hagerstown Nonattainment Areas

EPA is proposing to make a determination that the Metropolitan Washington, District of Columbia-Maryland-Virginia (DC-MD-VA) and Martinsburg-Hagerstown, West Virginia-Maryland (WV-MD) fine particle (PM<INF>2.5</INF>) nonattainment areas (hereafter referred to as "Areas") have attained the 1997 annual PM<INF>2.5</INF> National Ambient Air Quality Standard (NAAQS) by the applicable attainment date of April 5, 2010. These determinations are based upon complete, quality-assured, and certified ambient air monitoring data for the 2007-2009 monitoring period. EPA is finding these Areas to be in attainment, in accordance with the requirements of the Clean Air Act (CAA).